EP4673733A1 - Unité de capteur et circuit de résonateur associé - Google Patents

Unité de capteur et circuit de résonateur associé

Info

Publication number
EP4673733A1
EP4673733A1 EP24763363.9A EP24763363A EP4673733A1 EP 4673733 A1 EP4673733 A1 EP 4673733A1 EP 24763363 A EP24763363 A EP 24763363A EP 4673733 A1 EP4673733 A1 EP 4673733A1
Authority
EP
European Patent Office
Prior art keywords
sensor unit
ensemble
split
split ring
resonator
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
EP24763363.9A
Other languages
German (de)
English (en)
Inventor
Yechel BEN SHALOM
Nir BAR-GILL
Nissan MASKIL
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Elta Systems Ltd
Original Assignee
Elta Systems Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Elta Systems Ltd filed Critical Elta Systems Ltd
Publication of EP4673733A1 publication Critical patent/EP4673733A1/fr
Pending legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R33/00—Arrangements or instruments for measuring magnetic variables
    • G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
    • G01R33/24—Arrangements or instruments for measuring magnetic variables involving magnetic resonance for measuring direction or magnitude of magnetic fields or magnetic flux
    • G01R33/26—Arrangements or instruments for measuring magnetic variables involving magnetic resonance for measuring direction or magnitude of magnetic fields or magnetic flux using optical pumping
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R33/00—Arrangements or instruments for measuring magnetic variables
    • G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
    • G01R33/28—Details of apparatus provided for in groups G01R33/44 - G01R33/64
    • G01R33/32—Excitation or detection systems, e.g. using radio frequency signals
    • G01R33/34—Constructional details, e.g. resonators, specially adapted to MR
    • G01R33/34046—Volume type coils, e.g. bird-cage coils; Quadrature bird-cage coils; Circularly polarised coils
    • G01R33/34061—Helmholtz coils

Definitions

  • the present disclosure is in the field of microwave resonators and specifically relates to resonator for microwave control of spin ensembles.
  • Detecting RF electromagnetic radiation is essential for modern-day communication.
  • the conventional technique uses the interaction between radiation and electrons in conductive or semiconductive materials, based on classical electromagnetism, enabling detection of strong signals.
  • quantum interactions between photons and specific material properties can detect signal photon radiation and their properties.
  • Color centers are crystalline defects that introduce additional light absorption or emission.
  • a common type of color center used in various quantum metrology applications utilizes a Nitrogen Vacancy (NV) defect in diamond crystals.
  • the NV center is a nanoscale defect that can be initialized via optical pumping, readout by detection of fluorescent emission and undergo coherent manipulation using microwave (MW) fields.
  • color center in crystals and specifically NV centers in diamond, make these centers suitable candidates for detection of electromagnetic radiation and magnetic fields in general. Further, coherent manipulation of color center state enables enhanced detection properties.
  • Split ring resonators are artificial electromagnetic structures used in radio frequency and microwave engineering to create resonant circuits.
  • the structure of SRR circuits include one or more metallic rings that are split into two halves with a small gap between them, creating a capacitance and inductance (LC) circuit. The two halves of the ring are also separated by a small gap, creating an inductance.
  • Split ring resonators have certain properties that make them useful in various applications. For example, SRRs can be used to create metamaterials that have negative refractive index, form lenses that can focus non-optical electromagnetic radiation.
  • Split ring resonators are also used in microwave engineering to form band-stop and/or bandpass filters, which are used to block or allow certain frequencies of electromagnetic radiation. Further, SRRs are used in antenna design to improve the performance of antennas, e.g., by increasing the bandwidth or reducing the size of the antenna.
  • Split-ring resonators operate as LC circuits having a specific resonance frequency, determined by its size and shape of the ring. This enables the SRRs to interact with an incident electromagnetic wave by creating a phase shift in the wave's electric field, e.g., generating the appearance of a negative permittivity and permeability, effectively changing the properties of EM waves in the metamaterial etc.
  • the split-ring shape allows for inductive and capacitive coupling to create the resonant behavior, making it a useful component in the design of metamaterials for various applications, such as negative index metamaterials, microwave filters, and sensing.
  • WO 2022/079,713 describe a sensor system comprising: a plurality of sensor units arranged in a predetermined arrangement to be exposed to an electromagnetic signal to be measured, a drive unit configured for providing one or more electromagnetic drive pulses to said sensing units to thereby affect one or more selected quantum properties associated with said plurality of sensor units, and an optical detector unit configured for detecting variation in one or more optical properties of the sensor units in response to input collected electromagnetic radiation; wherein said drive unit is configured to apply the electromagnetic drive pulses having a predetermined phase function on said plurality of sensor units.
  • N Nitrogen-vacancy defect centers in diamond are promising solid-state magnetometers. Single centers allow for high-spatial-resolution field imaging but are limited in their magnetic field sensitivity. Using defect-center ensembles, sensitivity can be scaled with N when N is the number of defects. In the present work, we use an ensemble of N ⁇ 10n defect centers within an effective sensor volume of 8.5x10-4 mm3 for sensing at room temperature.
  • the present disclosure provides a sensor unit and corresponding resonator circuit configured to utilize an ensemble of color centers and apply generally uniform microwave driving to the ensemble of color centers.
  • the resonator circuit comprises a first and a second split rings having respective first and second diameters.
  • the first and second split rings are positioned in respective first and second parallel planes, allowing placement of one or more crystal structures carrying an ensemble of color centers in an intermediate plane between said first and second parallel planes.
  • the first and second split rings generate an effective cylindrical volume and provide a generally uniform magnetic field within at least a portion of the volume, allowing uniform coherent manipulation of the ensemble of color center.
  • the present disclosure provides a sensor unit comprising at least one crystal structure comprising an ensemble of color centers, and a resonator arrangement for applying selected magnetic field on said ensemble of color centers; said resonator comprises a first split ring having a first diameter and a second split ring having a second diameter; wherein said first split ring and said second split ring are positioned within first and second parallel planes, and wherein said at least one crystal structure is located in an intermediate plane between said first and second parallel planes.
  • the first and second split rings may define a virtual cylindrical space between them, and said at least one crystal structure is located within volume of said virtual cylindrical space.
  • the at least one crystal may be a diamond crystal, and said ensemble of color centers comprise a plurality of Nitrogen Vacancy centers within said diamond crystal.
  • a gap within said first split ring and a gap within said second split ring are placed at opposing orientations.
  • a gap within said first split ring and a gap within said second split ring are placed at 180 degrees respective orientation.
  • a distance between said first and second parallel planes may be in a range between 0.1mm and 20mm.
  • the distance between said first and second parallel planes may be for example 0.5 ⁇ 0.05mm, or 0.6+0.05mm, or 0.7+0.05mm, or 0.8+0.05mm or 0.9+0.05mm or l+0.05mm, or l.l+0.05mm, or 1.2+0.05mm, or 1.3+0.05mm, or 1.4+0.05mm, or 1.5+0.05mm, or 1.6+0.05mm.
  • the distance between said first and second parallel planes may be 0.4+0.05mm, or 0.3+0.05mm, or 0.2+0.05mm, or 0.1+0.05mm.
  • the first and second diameters of said first and second split rings are similar.
  • the first and second diameters of said first and second split rings may be in a range between 0.5mm and 20mm.
  • the first and second diameters may be 0.5mm, or 1mm or 2mm, or 3mm, or 4mm, or 5mm, or 6mm, or 7mm, or 8mm, or 9mm, or 10mm.
  • the first and second diameters may be selected in accordance with physical parameters of the first and second split rings to obtain a desired resonance frequency.
  • the sensor unit may be formed on a printed circuit board (PCB).
  • PCB printed circuit board
  • the first and second split rings may form a resonator having resonance frequency within a range between 0.5GHz and 50GHz.
  • the resonance frequency may be selected to be between 0.5GHz and 12GHz.
  • the resonance frequency may be determined in accordance with frequency of color centers used in the sensor.
  • the sensor unit may further comprise a first lead associated with said first split ring and a second lead associated with said second split ring, said first and second leads provide excitation signal to respective one of said first and second split rings.
  • the sensor unit may further comprise at least one microwave signal generator connected using one or more switched to said first and second leads for driving said first and second split rings with one or more selected signals.
  • the sensor unit may further comprise at least one laser unit and optical arrangement adapted to provide selective optical excitation of said at least one crystal.
  • the sensor unit may further comprise a magnetic field generator adapted to provide static magnetic field onto said at least one crystal.
  • the magnetic field generator may be adapted to selectively vary magnitude of said static magnetic field.
  • the sensor unit may further comprise an optical collection arrangement and at least one detectors, said optical collection arrangement is positioned for collecting optical emission from said ensemble of color centers in said at least one crystal and direct said optical emission to be detected by said at least one detector.
  • the present disclosure provides a sensor array system comprising an array of sensor units comprising at least one sensor unit configured as described herein.
  • the present disclosure provides a sensor array system comprising an array of sensor units each sensor unit being configured as described herein.
  • the present disclosure provides a resonator circuit for applying electromagnetic excitation onto an ensemble of color centers comprising: first and second split rings having respective first and second diameters; said first and second split rings are positioned within respective first and second parallel planes, and at least one crystal structure carrying said ensemble of color centers located in an intermediate plane between said first and second parallel planes.
  • the ensemble of color centers is located within at least one diamond crystal, and said ensemble of color centers comprise a plurality of Nitrogen Vacancy centers within said diamond crystal.
  • a gap within said first split ring and a gap within said second split ring are placed at opposing orientations.
  • a gap within said first split ring and a gap within said second split ring are placed at 180 degrees respective orientation.
  • a distance between said first and second parallel planes is in a range between 0.1mm and 20mm. According to some embodiments, a distance between said first and second parallel planes is 0.5 ⁇ 0.05mm.
  • the distance between said first and second parallel planes may be for example 0.5+0.05mm, or 0.6+0.05mm, or 0.7+0.05mm, or 0.8+0.05mm or 0.9+0.05mm or l+0.05mm, or 1.1+0.05mm, or 1.2+0.05mm, or 1.3+0.05mm, or 1.4+0.05mm, or 1.5+0.05mm, or 1.6+0.05mm. in some embodiments, the distance between said first and second parallel planes may be 0.4+0.05mm, or 0.3+0.05mm, or 0.2+0.05mm, or 0.1+0.05mm.
  • the first and second diameters of said first and second split rings may be similar. According to some embodiments, the first and second diameters of said first and second split rings may be in a range between 0.5mm and 20mm. For example, the first and second diameters may be 0.5mm, or 1mm or 2mm, or 3mm, or 4mm, or 5mm, or 6mm, or 7mm, or 8mm, or 9mm, or 10mm. The first and second diameters may be selected in accordance with physical parameters of the first and second split rings to obtain a desired resonance frequency.
  • the resonator circuit may be formed on a printed circuit board (PCB).
  • PCB printed circuit board
  • the first and second split rings form a resonator having resonance frequency within a range between 0.5GHz and 100GHz.
  • the resonance frequency may be selected to be between 0.5GHz and 50GHz.
  • the resonance frequency may be selected to be between 0.5GHz and 12GHz.
  • the resonance frequency may be determined in accordance with frequency of color centers used in the sensor.
  • the resonator circuit may further comprise a first lead associated with said first split ring and a second lead associated with said second split ring, said first and second leads provide excitation signal to respective one of said first and second split rings.
  • the resonator circuit may further comprise at least one microwave signal generator connected using one or more switched to said first and second leads for driving said first and second split rings with one or more selected signals.
  • the resonator circuit may further comprise at least one laser unit and optical arrangement adapted to provide selective optical excitation of said at least one crystal.
  • the resonator circuit may further comprise a magnetic field generator adapted to provide static magnetic field onto said at least one crystal.
  • the magnetic field generator may be adapted to selectively vary magnitude of said static magnetic field.
  • the resonator circuit may further comprise an optical collection arrangement and at least one detector, said optical collection arrangement is positioned for collecting optical emission from said ensemble of color centers in said at least one crystal and direct said optical emission to be detected by said at least one detector.
  • the present disclosure provides a sensor array system comprising an array of resonator circuits comprising at least one sensor unit configured as described herein.
  • the present disclosure provides a sensor array system comprising an array of resonator circuits each resonator circuits being configured as described herein.
  • the present disclosure provides method for use in operation of electromagnetic sensor comprising an ensemble of color centers, the method comprising: providing a first split ring at a first plane at one side of said ensemble of color centers, where axial center of said first split ring aligns with center of said ensemble of color centers; providing a second split ring at a second plane at an opposite side of said ensemble of color centers, where axial center of said second split ring aligns with center of said axial center of said first split ring; providing selected excitation signal to said first and second split rings thereby applying corresponding selected magnetic field excitation to said ensemble of color centers, to thereby initiate said ensemble of color center at selected state for sensing electromagnetic signal impinging thereon.
  • the ensemble of color centers is an ensemble of Nitrogen Vacancy centers within a diamond.
  • Fig. 1 schematically illustrates certain elements of a sensor and resonator according to some embodiments of the present disclosure
  • Fig. 2 illustrates an additional example of sensor and resonator according to some embodiments of the present disclosure
  • Fig. 3 shows a three-dimensional illustration of a resonator structure according to some embodiments of the present disclosure
  • Fig. 3 illustrates a multi sensor arrangement according to some embodiments of the present disclosure
  • Fig. 4 shows design for simulated and fabricated resonator circuit and crystal structure according to some embodiments of the present disclosure
  • Fig. 5 shows z component of magnetic field generated by the resonator structure according to some embodiments of the present disclosure
  • Fig. 6 shows simulated response of resonator circuit according to some embodiments of the present disclosure to drive of different frequencies ;
  • Fig. 7 shows simulated data on response of resonance frequency to variation of construction parameters of a resonator circuit according to some embodiments of the present disclosure
  • Fig. 9 shows characteristics measured Rabi oscillations
  • Fig. 10 shows measurement of magnetic field inside the resonator according to some embodiments of the present disclosure as a function of input power
  • Fig. 11 shows measured reflection coefficient (Si l) for resonators according to some embodiments of the present disclosure having different ring radius
  • Fig. 12 shows measured inhomogeneity in field excitation by a resonator circuit according to some embodiments of the present disclosure.
  • Fig. 1 shows a schematic illustration of a resonator circuit 60, that may be used in a sensor unit 100 according to some embodiments of the present disclosure.
  • the sensor unit 100 utilizes a crystal structure 50 having a plurality of color centers 55 embedded therein.
  • the crystal structure 50 is positioned within a resonator circuit 60 formed by first 62 and second 64 split rings that are placed in respective first and second planes, generally above and below (or in two opposite sides) of the crystal structure 50.
  • color centers crystals such as Nitrogen Vacancy centers in diamonds
  • NV diamond defects may be used as high sensitivity detectors for electromagnetic radiation or in generally to varying magnetic fields.
  • the color centers may be manipulated using optical illumination, and magnetic fields to provide enhanced sensing with selected detection properties.
  • WO 2022/079,713 describes detection of electromagnetic radiation using color centers such as NV centers being coherently manipulated by microwave pulses.
  • Proper manipulation of the quantum state of color centers enables selection of the sensing properties and may be used for detection of phase information in collected varying magnetic fields (e.g., electromagnetic radiation).
  • magnetic fields e.g., electromagnetic radiation
  • applying selected magnetic of microwave manipulation on an ensemble of color centers poses a challenge in generating sufficiently uniform magnetic field.
  • the resonator configuration of the present disclosure provides generally uniform magnetic field in a desired volume within the resonator circuit allowing uniform coherent manipulation to an ensemble of color centers, and operation of the ensemble of color centers as a sensor unit for electromagnetic signals.
  • the resonator 60 of the present disclosure is formed of a first split ring 62 placed in a first plane, and a second split ring 64 placed in a second plane, being generally above of below the first split ring 62.
  • Each of the first 62 and second 64 split rings is formed of a conducting material in a ring shape and having a gap in conductivity around the ring.
  • the first 62 and second 64 split rings are generally aligned along a shared axial axis and being oriented with different, and preferably opposite gaps directions. This configuration forms an effective cylindrical volume located between the split rings 62 and 64 and defined by circumference of the split rings and distance between them.
  • the first 62 and second 64 split rings are coupled to respective first 72 and second 74 electrical leads positioned at close vicinity to the rings and configured to couple electrical signals thereto. More specifically, the first 72 and second 74 leads are connectable to an electronic circuit for directing electrical excitation of selected frequency and amplitude toward the respective first 62 and second 64 split rings.
  • the electrical excitation is coupled to the rings and generates corresponding excitation of the split rings, thereby generating current excitation flowing through the rings. This in turn generate magnetic field variation around the split rings.
  • Excitation of the first and second split rings with electrical signal having frequency close to resonance frequency of the split rings and having suitable phase relation between excitation of the first 62 split ring and the second 64 split ring can generate a magnetic field that varies with time and is spatially uniform within a volume between the split rings.
  • the resonator circuit 60 is adapted to hold a crystal structure 50 at a selected location between the first 62 and second 64 split rings.
  • dimensions of the resonator circuit 60 are determined in accordance with dimensions of the crystal structure 50 selected to operate therewith.
  • diameter of the first 62 and second 64 split rings may be determined to be larger than width or length of the crystal structure 50, and distance between the split rings along the axial axis thereof is determined to be larger than height of the crystal structure 50.
  • the dimensions are generally selected to allow placement of the crystal structure 50 within a region having generally spatially uniform magnetic field, while avoiding field variations at edges thereof.
  • first 62 and second 64 split rings may be of selected similar dimensions, including ring diameter, gap length, material thickness and material selection.
  • the material selection and split ring dimensions may be selected to provide a generally similar resonance frequency for the first 62 and second 64 split rings, to thereby enable generating combined magnetic field that is spatially uniform within the selected region between the rings.
  • the first 62 and second 64 split rings may have respective first and second diameters similar dimensions.
  • the first and second split rings may have diameters of said first and second split rings are in a range between 0.5mm and 20mm, and distance between the first and second split rings along the axial axis may be in the range between 0.1mm and 50mm, or preferably between 0.1mm and 20mm.
  • Additionally parameters that define resonance frequency of the first and second split rings include resistivity of the material, width of the conducting elements of the split rings, height of the split rings, gap distance, as well as excitation gap being a gap between the split rings 62 or 64 and conducting leads 72 or 74 providing electrical excitation thereto.
  • the resonator circuit 60 may be excited by electrical input directed via one lead, being lead 72 or 74, or via both leads simultaneously.
  • resonator circuit 60 is illustrated including a virtual cylindrical (or partly cone shaped) volume 40 defined by the first 62 and second 64 split rings. Crystal structure 50 is positioned within the virtual volume 40, typically centered on the axial axis of the first and second split rings, at mid distance between the split rings.
  • the sensor unit 100 may also include one or more additional units for controlling and modifying excitation of the ensemble of color centers 55. Such additional units may include one or more of: a statis magnetic field generator 80, a light source unit 90, and a light collection arrangement 95.
  • the static magnetic field generator 80 may be a permanent magnet, electromagnet or other devices configured to provide a generally statis magnetic field applied on the crystal structure 50 and the ensemble of color centers 55 embedded therein. Static magnetic field may be used to tune separation between spin states of the color centers.
  • a light source 90 may be used to provide optical illumination 92 for optically pumping the color centers. This may be sued for providing selected excited state of the color centers as known in the art for operating color centers such as NV centers in diamond crystals for detection of magnetic field or electromagnetic radiation.
  • Light collection arrangement 95 is generally used for collecting optical emission from the ensemble of color centers 55. Typically, detection of radiation using one or an ensemble of color centers is performed by detection of optical radiation emitted by the color centers.
  • the light collection arrangement may include a light guide arrangement, e.g., formed by coupling waveguide portion 94 and transmission waveguide portion 96, and optical detection unit 98.
  • the coupling waveguide portion 94 may be configured with a trapezoid section and is positioned with narrow face directed at the crystal structure 50.
  • the coupling waveguide portion 94 is connected to, and may be an integral part of, transmission waveguide section 96, which is configured to guide light coupled into the coupling waveguide portion 94 toward the detector 98.
  • Detector 98 is located at far end of the transmission waveguide 96 portion and configured to generate electrical signals in response to optical illumination impinging thereon.
  • the detector 98 may include one or more photodiodes and may be connected to a detection circuitry for collection of electrical signals indicative of detection thereby.
  • the sensor unit 100 may also include an electrical circuit for generating electrical excitations and transmitting the electrical excitation via first 72 and second 74 leads.
  • the sensor unit 100 may also include, or be associated with, a controller including one or more circuits for controlling operation of the various elements of the sensor 100 and for collecting and analyzing data on signals detected by the sensor unit 100.
  • the sensor unit 100 may be used as a single sensor arrangement, or in a sensor system including an arrangement of a plurality of sensor units.
  • Fig. 3 illustrates a sensor system 400 including an array 300 of sensor units 1001, 1002 to lOOn, and a controller 500.
  • the sensor units 1001 to lOOn generally include respective sensing elements such as crystal units having a plurality of color centers embedded within, e.g., using diamond crystals having a plurality of NV centers in each diamond.
  • the sensor units 1001 to lOOn include one or more sensor units associated with a resonator circuit as exemplified herein with respect to Figs.
  • sensor units 1001 to lOOn are configured as sensor unit 100 exemplified herein with respect to Figs. 1 and 2.
  • the array of sensors 300 may have any selected arrangement and geometry.
  • the array of sensors 300 may be a one-dimensional or two-dimensional array.
  • the array 300 may be operated for detection of spatial variations in electromagnetic radiation, e.g., using phased array techniques, and may include a readout circuit for collecting detection data from the plurality of sensor units 1001 to lOOn.
  • a design of the resonator circuit 60 according to some embodiments of the present disclosure is shown in Fig. 4.
  • This specific and not- limiting exemplary configuration was tested by simulation and experimental study to analyze parameters of magnetic field generated thereby.
  • the resonator circuit parameters were selected to provide resonance frequency around resonance frequency of NV centers in diamond that is 2.87GHz.
  • the simulations were conducted using a commercial finite elements electromagnetic analysis package (CST).
  • CST finite elements electromagnetic analysis package
  • the simulations were used to extract data on the Si l parameter relating to reflection coefficient, and the magnetic field at the center along the normal axis (z), as a function of the exciting frequency.
  • a crystal structure having thickness of about 0.5mm was simulated to be positioned within the resonator circuit.
  • the crystal structure was excited by laser excitation, exemplified by light source 90 in Fig. 2, directed through a selected one of the split rings.
  • This configuration provides an effective excitation volume having a generally cylindrical shape with a height of 0.5 mm and a diameter between 0.1mm and 1.5mm.
  • Figs. 5 to 7 showing parameters of the magnetic field excitations generated by the resonator circuit of the present disclosure.
  • Fig. 5 shows z component of microwave excitation generated by the resonator circuit 60;
  • Fig. 6 shows Si l response relating to reflection of electrical excitation transmitted to the resonator circuit;
  • Fig. 7 shows the effect of variation in resonator circuit parameters and respective resonance frequency.
  • the excitation field generated by the resonator circuit forms an excitation field that is generally uniform within the cylindrical volume.
  • the simulations include excitation transmitted through one or both of the split rings such that the average magnetic field within the cylindrical volume was determined to be 1.5Gauss/ Watt for single ring excitation, and 2Gauss/ Watt for excitation through both rings.
  • Inhomogeneity of the excitation field is defined herein as the standard deviation of the magnetic field, normalized by its mean value.
  • Simulation of the resonator circuit described herein indicate an inhomogeneity of 0.43% for diameter of 0.5mm and excitation transmission through both the split ring (dual drive), or 0.71% for similar diameter and excitation transmission though one of the split rings (single drive).
  • Fig. 6 shows reflection (Sil) curve for excitation as a function of excitation frequency and so-generated excitation field magnitude (Hz).
  • the resonator circuit provides different resonances.
  • the resonance of lower frequency (R+) is symmetric with both loops driven by current along the same direction.
  • the higher frequency resonance (R-) is anti-symmetric with current driving in opposite directions in the two rings.
  • the symmetric resonance R+ generates magnetic field along the normal axis as shown in Bz graph. This is while current directions in the R- resonance cancel the z component of the magnetic field at location of the crystal structure.
  • Fig. 7 exemplifies results of simulation data on variation in the effect of several parameters on the position of the symmetric resonance R+.
  • the parameter varied include radium of the split rings, width, distance between the split rings along the z axis (distance between planes) and width of the slit/gap of the split rings.
  • variation of split rings radium leads to the most significant variation in resonance frequency of the resonator circuit.
  • Radius variation leads to a sensitivity of the resonance to the radius of 1006MHz/mm, while the greater the radius, the lower the resonance frequency.
  • Additional design parameters that vary the resonance frequency include the distance between the first and second split rings that generate resonance frequency sensitivity of 67MHz/mm, variation of the width of the strip of the first and second split rings that varies the resonance frequency with sensitivity of - 136MHz/mm, and the gap defined by the split in the split rings that varies the resonance frequency with a sensitivity of 366MHz/mm.
  • selection of resonator parameters and variation thereof may be used for tunning resonance frequency of the resonator. While the specific sensitivity to selected parameters may vary with specific resonator design, this exemplary data may suggest design parameters for optimization of the resonance frequency.
  • the circuit was fabricated on printed circuit board.
  • the circuit was fabricated on Rogers 6010.2LM PCB board selected for its high dielectric constant.
  • the fabricated circuit is designed as illustrated in Fig. 4 above.
  • the fabricated resonator circuit was used for several characterization measurements performed using a scanning confocal microscope on a relevant, high NV density diamond sample.
  • Optical excitation was provided by a 532nm diode-pumped solid-state (DPSS) laser (Laser Quantum axiom 532) focused onto the diamond using a lOx, 0.25NA objective.
  • the excitation laser was pulsed by focusing it through an acoustic-optical modulator (G&H R15260).
  • NV fluorescence was collected through the same objective and separated from the excitation beam using a dichroic filter (Semrock Di02-R635- 25X36).
  • the light was additionally filtered (using a Thorlabs high-pass FELH0650 and notch NF533-17) and focused onto a single -photon counting module (Excelitas Technologies SPCM-780-13-FC).
  • the resonator was driven by an amplified (Minicircuits ZHL-16W-43-S+) MW generator (Windfreak synthHD) and modulated by a switch (Mini-circuits ZASW-2- 50DRA+).
  • Microwave and optical pulses were controlled using a computer-based digital delay generator (Swabian Instruments Pulse-Streamer). Measurement protocols (pulse sequences, data acquisition, etc.) were controlled by custom software.
  • the static magnetic field was applied with a permanent magnet whose distance and position relative to the NV center were controlled by three translation stages.
  • the diamond position was controlled by 3 piezo-electric stages.
  • the diamond sample used in these experiments was model DNV-B 1 (Element Six), with an NV density of ⁇ 300 ppb.
  • the resonator circuit was first characterized using a MW network analyzer, measuring the resonance and S parameters.
  • Fig. 9 shows characteristic Rabi oscillations of NV center in the resonator circuit.
  • Fig. 10 shows measurement of magnetic field inside the resonator as a function of input power.
  • Fig. 11 shows measured reflection coefficient (Si l) for resonators having different ring radius.
  • the Rabi oscillations were measured in order to analyze the field homogeneity.
  • a characteristic Rabi oscillation curve at a power of 9Watt is shown in Fig. 9.
  • the magnetic field generated by the resonator was measured at 8 different points at different distances from the axial center as shown in Fig. 10 for dual-port drive (solid) and single -port drive (dashed) and for different input power. These measurements show good agreement with the simulation for different design parameters indicating the ability to vary resonator parameters for selected resonance and field characteristics.
  • the Rabi frequency was determined at a plurality of points inside the resonator.
  • the selected measurement points were arranged at equal distances from the center along a radial axis of the resonator. Measurement at each point was repeated for 4 points along the Z axis. Each point was measured both with dual drive excitation and with a single port. Finally, the standard deviation for each radius was determined with a weight term that takes into account the different distances between the points.
  • Fig. 12 shows simulated, and experimental field inhomogeneity of the magnetic field measured within the resonator circuit.
  • the present disclosure provides a sensor unit and a resonator circuit configured to provide a generally uniform magnetic field excitation.
  • the resonator circuit is capable of applying uniform magnetic field excitation to an ensemble of color centers, such as NV centers, thus allowing for sensor with increased sensitivity and specificity.

Landscapes

  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Measuring Magnetic Variables (AREA)
  • Optical Modulation, Optical Deflection, Nonlinear Optics, Optical Demodulation, Optical Logic Elements (AREA)

Abstract

L'invention concerne une unité de capteur et un circuit de résonateur. L'unité de capteur comprend au moins une structure cristalline comportant un ensemble de centres colorés, et un agencement de résonateur pour appliquer un champ magnétique sélectionné sur l'ensemble de centres colorés. L'agencement de résonateur comprend un premier anneau fendu avec un premier diamètre et un second anneau fendu avec un second diamètre. Les premier et second anneaux fendus sont positionnés à l'intérieur de premier et second plans parallèles, et ladite au moins une structure cristalline est située dans un plan intermédiaire entre lesdits premier et second plans parallèles.
EP24763363.9A 2023-02-28 2024-02-26 Unité de capteur et circuit de résonateur associé Pending EP4673733A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IL301049A IL301049A (en) 2023-02-28 2023-02-28 A sensor unit and resonator circuit thereof
PCT/IL2024/050217 WO2024180541A1 (fr) 2023-02-28 2024-02-26 Unité de capteur et circuit de résonateur associé

Publications (1)

Publication Number Publication Date
EP4673733A1 true EP4673733A1 (fr) 2026-01-07

Family

ID=92589315

Family Applications (1)

Application Number Title Priority Date Filing Date
EP24763363.9A Pending EP4673733A1 (fr) 2023-02-28 2024-02-26 Unité de capteur et circuit de résonateur associé

Country Status (3)

Country Link
EP (1) EP4673733A1 (fr)
IL (1) IL301049A (fr)
WO (1) WO2024180541A1 (fr)

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US12287201B2 (en) * 2020-01-27 2025-04-29 Michael Stern Magnetometer and method for finding a magnitude of an ambient magnetic field or of one or more components thereof

Also Published As

Publication number Publication date
WO2024180541A1 (fr) 2024-09-06
IL301049A (en) 2024-12-01

Similar Documents

Publication Publication Date Title
Sasaki et al. Broadband, large-area microwave antenna for optically detected magnetic resonance of nitrogen-vacancy centers in diamond
Fu et al. Direct visualization of electromagnetic wave dynamics by laser-free ultrafast electron microscopy
Le Floch et al. Rigorous analysis of highly tunable cylindrical transverse magnetic mode re-entrant cavities
CN101568849B (zh) 用于mr成像系统中的结合了元材料的rf线圈
Eisenach et al. Broadband loop gap resonator for nitrogen vacancy centers in diamond
US20170010338A1 (en) Optically detected magnetic resonance imaging with an electromagnetic field resonator
JP6367236B2 (ja) 電子スピン共鳴用共鳴装置
Kapitanova et al. 3D uniform manipulation of NV centers in diamond using a dielectric resonator antenna
CN109490804B (zh) 高频磁场产生装置
Aslam et al. Single spin optically detected magnetic resonance with 60–90 GHz (E-band) microwave resonators
CN110462417A (zh) 包括自旋缺陷的扫描传感器
JP7112652B2 (ja) 高周波磁場発生装置
Yaroshenko et al. Circularly polarized microwave antenna for nitrogen vacancy centers in diamond
Kunert et al. A planar ion trap chip with integrated structures for an adjustable magnetic field gradient
Soshenko et al. Microwave antenna for exciting optically detected magnetic resonance in diamond NV centers
Crocco et al. On embedded microwave imaging systems: retrievable information and design guidelines
WO2024180541A1 (fr) Unité de capteur et circuit de résonateur associé
JP4682022B2 (ja) 周期構造体、周期構造体を用いた素子、及び周期構造体の作製方法
JPH09205319A (ja) 準光学共振器を用いたミリ波サブミリ波用装置
WO2021014354A1 (fr) Appareil de résonance magnétique nucléaire faisant appel à des métamatériaux ou à des matériaux diélectriques
JP7327808B2 (ja) 平面ループギャップ共振器、量子センシングシステム及び量子磁気センサーユニット
Usanov et al. Near-field microwave microscopy. Capabilities. Application areas
Nishitani et al. Loop-gap microwave resonator for millimeter-scale diamond quantum sensor
RU217818U1 (ru) Подложка конфокального микроскопа для измерения оптически детектируемого магнитного резонанса
Eisenach Tunable and broadband loop gap resonator for nitrogen vacancy centers in diamond

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20250901

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC ME MK MT NL NO PL PT RO RS SE SI SK SM TR