EP0873532A1 - Commutateur de mach-zehnder - Google Patents

Commutateur de mach-zehnder

Info

Publication number
EP0873532A1
EP0873532A1 EP96916609A EP96916609A EP0873532A1 EP 0873532 A1 EP0873532 A1 EP 0873532A1 EP 96916609 A EP96916609 A EP 96916609A EP 96916609 A EP96916609 A EP 96916609A EP 0873532 A1 EP0873532 A1 EP 0873532A1
Authority
EP
European Patent Office
Prior art keywords
fiber
mach
phase shift
pump power
accordance
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.)
Withdrawn
Application number
EP96916609A
Other languages
German (de)
English (en)
Other versions
EP0873532A4 (fr
Inventor
William J. Miller
Daniel A. Nolan
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.)
Corning Inc
Original Assignee
Corning Inc
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 Corning Inc filed Critical Corning Inc
Publication of EP0873532A1 publication Critical patent/EP0873532A1/fr
Publication of EP0873532A4 publication Critical patent/EP0873532A4/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/35—Non-linear optics
    • G02F1/3515—All-optical modulation, gating, switching, e.g. control of a light beam by another light beam
    • G02F1/3517—All-optical modulation, gating, switching, e.g. control of a light beam by another light beam using an interferometer
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/29—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the position or the direction of light beams, i.e. deflection
    • G02F1/31—Digital deflection, i.e. optical switching
    • G02F1/313—Digital deflection, i.e. optical switching in an optical waveguide structure
    • G02F1/3136—Digital deflection, i.e. optical switching in an optical waveguide structure of interferometric switch type
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/10—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type
    • G02B6/12—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type of the integrated circuit kind
    • G02B2006/12133—Functions
    • G02B2006/12145—Switch
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/2804—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals forming multipart couplers without wavelength selective elements, e.g. "T" couplers, star couplers
    • G02B6/2821—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals forming multipart couplers without wavelength selective elements, e.g. "T" couplers, star couplers using lateral coupling between contiguous fibres to split or combine optical signals
    • G02B6/2835—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals forming multipart couplers without wavelength selective elements, e.g. "T" couplers, star couplers using lateral coupling between contiguous fibres to split or combine optical signals formed or shaped by thermal treatment, e.g. couplers
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/293—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
    • G02B6/29346—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by wave or beam interference
    • G02B6/2935—Mach-Zehnder configuration, i.e. comprising separate splitting and combining means
    • G02B6/29352—Mach-Zehnder configuration, i.e. comprising separate splitting and combining means in a light guide
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/29—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the position or the direction of light beams, i.e. deflection
    • G02F1/31—Digital deflection, i.e. optical switching
    • G02F1/313—Digital deflection, i.e. optical switching in an optical waveguide structure
    • G02F1/3131—Digital deflection, i.e. optical switching in an optical waveguide structure in optical fibres

Definitions

  • the present invention relates to optical power switching devices.
  • Optical switches with switching speeds up to 1 gigahertz are required for numerous applications including local area networks, sensor arrays and communications systems.
  • Many forms of optical switching devices have been developed. Typical examples are multiple-quantur.- well waveguide switches, strained-layer superlattice directional couplers and optical fiber switches. These devices are based on the nonlinear effect of the material that forms them. In the case of semiconductor devices, the required critical power for a switch is less than 1 .
  • optical fiber switches had been fabricated from optical fibers having silica based ceres. The optical power required for these optical fiber switches is on the order of several kilowatts since the nonlinear coefficient of silica is extremely small.
  • Pantell et al. describe an experiment in which a 3.4 m length of two-mode fiber was utilized. A phase shift of ⁇ required an absorbed pump power of 15.5 m . The signal was launched to inject approximately equal powers in the LP 01 and LP :: modes. This type of signal injection is difficult to impliment, and the device is unstable with respect to external vibrations and perturbations.
  • One or both fibers in the phase shift region of the Mach-Zehnder device of Pantell et al. is made of Erbiu - doped fiber, the pump power being coupled into only one of the . Since it is stated at page 1417 that the pump power requirement of a two mode fiber (TMF) switch is generally larger than for an equivalent Mach-Zehnder (MZ) switch by a factor of 2-4, it follows that a Mach-Zehnder switch of this type would be about 85 to 170 cm long provided that the power remained constant. In the absence of pump power all of the signal power appears at output port 2. When sufficient pump power is applied to cause a phase difference of ⁇ , the signal switches to output port 3. Pantell et al. indicate that the fiber core is heated due to the generation of phonons by the pump power in the fiber core and that the two mode fiber is advantageous over the Mach-Zehnder interferometer since the two modes utilize the same guiding region and therefore react similarly to environmental changes.
  • the .Pantell two-mode device is very sensitive to the launch condition and any perturbations along the length of the two mode fiber. Also, it is not directly compatible with single-mode operation. In order to attain compactness and ease of handling, it would be advantageous for nonlinear switches of the Mach-Zehnder type to be formed as a monolithic structure. For such devices to be practical, their length should not exceed about 15 cm.
  • obj ect of the present invention to provide an optical switch that overcomes the heretofore noted disadvantages of prior art switches .
  • a further obj ect is to provide a compact, low power, low cross-talk nonlinear optical switch .
  • the monolithic Mach-Zehnder switch of the present invention comprises input coupler means for splitting an input signal into N equal signal components . where N>1.
  • Combining means having at least first and second output terminals, is provided for combining the N components.
  • N optical waveguide paths connect the N signal components to the combining means. At least one of the waveguide paths contains a material having a resonant nonlinearity, whereby its refractive index changes when pump power propagates through it.
  • the input coupler means and the combining means are free from nonlinear material.
  • the input coupler means, the combining means and the optical waveguide paths are in thermal contact with a matrix glass body.
  • the switch consists of first and second optical fibers extending longitudinally through an elongated body of matrix glass.
  • the body includes a phase shift region and two spaced coupler regions at opposite ends of the phase shift region.
  • the diameter of the body and the diameters of the fibers are smaller in the coupler regions than in the phase shift region
  • At least that portion of the first fiber that is in the phase shift region contains a material having a resonant nonlinearity, whereby the refractive index of the first fiber changes when pump power propagates through it.
  • the fibers have different propagation constants in the phase shift region in the absence of pump power propagating through the first fiber so that the first fiber subjects the light propagating therethrough to a delay that is different from the delay experienced by light propagating through the second fiber.
  • Fig. 1 is a schematic diagram of a prior art Mach- Zehnder switch.
  • Fig. 2 is a plot of power output vs. wavelength for two types of Mach-Zehnder devices.
  • Fig. 3 is a plot of the power (P s ) required for switching as a function of wavelength separation between adjacent peaks and valleys of curve of Fig. 2.
  • Fig. 4 is a cross-sectional view of a Mach-Zehnder switch formed in accordance with the present invention.
  • Fig. 5 is a cross-sectional view taken along lines 5- 5 of Fig. 4.
  • Fig. 6 is a graph illustrating loss vs. launch power for a -Mach-Zehnder switch formed in accordance with the present invention.
  • Fig. 7 shows a planar Mach-Zehnder switch.
  • a Mach-Zehnder switch of the type disclosed in the aforementioned Pantell et al. publication is schematically illustrated in Fig. 1.
  • Two couplers 11 and 12 are concatenated by waveguide paths 14 and 15.
  • the couplers are usually 3 DB couplers, whereby the signal power that is applied to input port 2, for example, is evenly divided between the two outputs of coupler 11.
  • One or both of waveguide paths 14 and 15 contains a material having a resonant nonlinearity, whereby a refractive index change is induced by absorption of light within a predetermined wavelength band.
  • the rare earth elements are particularly suitable since they exhibit large nonlinear refractive indices.
  • the rare earth element erbium exhibits a very large nonlinear index.
  • neodimium as the nonlinear material would increase switching speed, but more switching power would be required.
  • dopants with which a population inversion can be achieved in order to provide a resonant nonlinearity. Examples include the transition metals such as chromium and titanium.
  • the light absorbed by the nonlinear material can be a pump or gating pulse having a wavelength different from that of the signal. Alternatively, the signal wavelength can be within that band of wavelengths that induces an index change in the nonlinear material.
  • separate signal and gating pusles can be applied to one or both input ports, or a single signal pulse can be applied to one input port (as in the case of a power limiter) , its amplitude determining whether switching occurs, i.e. it determines the output port at which the output signal appears.
  • waveguide path 14 is the nonlinear path. Pump power is shown as being applied to input port 1, and the signal is shown as being applied to input port 2. If desired, both pump and signal power could be applied to the same input port.
  • the characteristics of coupler 11 are such that essentially all of the pump power applied to input port 1 remains uncoupled whereby it propagates only in waveguide path 14. In the absence of pump power applied to input port 1, the signal appears at output port 3. This is accomplished by appropriately fixing the phase shift between the two waveguide paths 14 and 15.
  • the pump power causes a change in refractive index in waveguide path 14 such that when the pump is turned on with enough power to induce a phase shift of ⁇ , the signal fully switches from output port 3 to output port 4.
  • the nonlinear path exist only in the phase shift region rather than continue into and form part of the couplers so that the coupling characteristic is not affected by pump power.
  • Another important advantage of this configuration is that it enables the use of relatively high loss doped fibers or waveguides to achieve nonlinearity, but since the doped fiber exists only between the couplers, loss is minimized. If the nonlinear material extends through the couplers, then the ⁇ pump power should be applied to the fiber or path that does not contain nonlinear material, the pump power being coupled to the nonlinear fiber; this would minimize loss.
  • publication optical waveguide paths 14 and 15 are relatively long, and problems arise as a result of the heating of the nonlinear path 14 when pump power propagates through it.
  • the heating problem is alleviated by forming the device as a monolithic structure whereby heat generated by the nonlinear arm of the phase-shift region is conducted to the remaining arm of the phase-shift region.
  • Such a monolithic Mach-Zehnder device can be in the form of an overclad fiber structure or a planar circuit.
  • the length of the conventional device of Fig. 1 is such that it is not suitable for such monolithic devices. For such monolithic devices to be practical, their length should not exceed about 15 cm.
  • a second feature of the invention results in nonlinear switching at significantly lower power levels (up to two orders of magnitude lower than with the conventional design disclosed in the Pantell et al. publication) . Since there is a tradeoff between length of nonlinear fiber and switching power, this second feature can be employed to render the phase-shift region sufficiently short that the entire device is easily fabricated as an overclad or planar structure. That is, the device can be shortened to an acceptable length, and the switching power can be correspondingly maintained at a relatively low level.
  • Output power is plotted in Fig. 2 as a function of wavelength for two different single-stage Mach-Zehnder devices.
  • Curve 21 represents the output for a device in which the propagation constants of the two fibers in the phase shift region are substantially equal.
  • Curve 22 represents the output for a device in which the propagation constants of the two fibers in the phase shift region are significantly different. Whereas curve 22 includes a plurality of peaks within the wavelength range shown, curve 21 is representative of a broadbanded characteristic, whereby only its peak appears within the wavelength range covered by Fig. 2.
  • the model discussed below shows that the amount of power required to cause a signal to switch between the two output ports of a Mach-Zehnder device is a function of the wavelength separation between a peak 26 and and an adjacent valley 25, for example, of curve 22 of Fig. 2 and thus, the difference between the propagation constants of waveguide paths 14 and 15.
  • the model assumes that waveguide paths 14 and 15 in the phase shift region of Fig. 1 have different effective indices.
  • the model assumes that the nonlinear material is silica, similar results would be obtained if it were silica doped with a material that enhanced the nonlinear property of the waveguide path.
  • n 2 and n represent effective indices of propagation in path 1 and path 2, respectively, and ⁇ is the signal wavelength.
  • the length z of waveguide paths 14 and 15 is chosen so that a ⁇ /2 phase change is introduced between the two wavelengths of interest. If, for example, it is assumed that a minimum is to occur at wavelength ⁇ : (point 26 of Fig. 2) and a maximum is to occur at wavelsngth ⁇ 2 (point 25 of Fig. 2), z is given by
  • the required power (in watts) for switching is approximately
  • Fig. 3 is a plot of the the power (P s ) required for switching as a function of the PP Band, which is the low
  • An overclad Mach-Zehnder switch can be formed in accordance with the teachings of U.S. patent No. 5,295,205 which is incorporated herein by reference.
  • the monolithic structure of Figs. 4 and 5 contains concatenated overclad couplers 41 and 42 that are joined by a phase shifting region 44.
  • the device is formed by inserting optical fibers 46 and 47 into the bore 48 of a tube of matrix glass 49. Each of the optical fibers has a core surrounded by cladding of refractive index lower than that of the core.
  • fiber 46 is a single piece of fiber, and fiber 47 consists of sections 47a, 47b and 47c which are fused together prior to making the device.
  • Section 47a, which is located in phase shift region 44, is doped with rare earth ions, while sections 47b and 47c do not contain rare earth ions. That portion of fiber 46 that is located in the phase shift region is designated 46a.
  • the difference in propagation constants ⁇ between the two fibers in the phase shift region 44 in the absence of pumping or switching power must be sufficient to enable switching at low power levels as discussed above.
  • Any technique for obtaining different propagation constants can be employed.
  • the diameter of the core of fiber 47a can be smaller than that of fiber 46a as shewn in Fig. 5.
  • the different density of dots in the cores of fibers 46 and 47 illustrates that the core of fiber 47a contains rare earth ions.
  • the fiber cores could have different refractive indices, or the fiber claddings could have different refractive indices or diameters. Any two or more of these features can be combined to obtain a difference in propagation constants. Assuming the aforementioned maximum acceptable length of 15 cm and pump or switching power of less than 1 mW, then ⁇ would be equal to or greater than 0.003.
  • the refractive index of that portion of the matrix glass tube adjacent the fibers is less than the lowest refractive index of either of the fiber claddings.
  • the bore can be provided with funnels (not shown) at each end to facilitate insertion of the fibers.
  • the combination of tube and fibers is referred to as a coupler preform.
  • That portion of the tube between points a and b is initially heated and collapsed onto the fibers and is at least partially fused to them. Also, the fibers are caused to contact one another, whereby there is good thermal conductivity between them. This can be accomplished by evacuating the tube bore, heating the tube near a first end 53 to cause it to collapse at the region of applied heat, and moving the preform relative to the heat source to gradually extend the collapsed region toward end 54 until the desired length of collapsed tube is obtained. Thereafter, coupler 41 is formed near end 53 of the tube by heating a region of the tube and moving those sections of the tube on opposite sides of the hot zone in opposite directions to stretch the heated region. The stretching operation is stopped after a predetermined coupling is achieved. While stretching the tube to form the first coupler, optical power can be coupled to an input optical fiber, and the output signals can be monitored to control process steps in the coupler manufacturing process.
  • couplers 41 and 42 have substantially identical coupling characteristics over the wavelength band of interest.
  • the second coupler 42 is therefore preferably formed near tube end 54 by subjecting the appropriate region of the tube to stretching conditions that are identical to those used to form the coupler 41.
  • Tube 10 was comprised of silica doped with 5 wt. % boron.
  • Fiber 46 was a standard single-mode fiber having an outside diameter of 125 ⁇ m and a core diameter of 9 urn.
  • the fiber cladding was formed of silica, and the core was formed of silica doped with a sufficient amount of germania to provide a core-clad ⁇ of 0.35%.
  • Fiber 47 consisted of a single piece of erbium-doped fiber having an outside diameter of 125 ⁇ m and a core diameter of 4 ⁇ m.
  • the fiber cladding was formed of silica, and the core was formed of silica doped with 1000 pp by weight erbium and a sufficient amount of germania to provide a core-clad ⁇ of approximately 1.0 %.
  • the tube was collapsed onto the fibers and stretched to form couplers 41 and 42 in accordance with the above- described method.
  • the couplers were 3dB at 1550 nm.
  • the overall length of the resultant device was 12.7 cm.
  • the peak to valley wavelength separation (see Fig. 2) of the Mach-Zehnder switch was 6 nm in the absence of pump power.
  • a laser diode operating at 1521 nm was connected to input port 2 by an attenuator.
  • Fig. 6 shows the output of the device as a function input power.
  • Curve 61 represents the device excess loss.
  • Curve 62 represents the insertion loss between input port 2 and output port 4, and curve 63 represents the insertion loss between input port 2 and output port 3.
  • Fig. 6 shows that switching occurred at an input power of less than one milliwatt.
  • the specific example shows that the amount of power needed 5 to cause a signal to switch between the two output ports 3 and 4 of Fig. 1 depends on the phase difference already existing between the two arms 14 and 15 of the phase shift region before the pump or gating pulse is introduced.
  • Fig. 7 shows that embodiment in which the Mach-
  • 10 Zehnder switch is formed as a planar device. All waveguide paths and couplers are formed in or on substrate 66. Input paths 71 and 72 are connected to phase shift paths 69 and 70 by coupler 68. Paths 69 and 70 are connected to output paths 73 and 74 by coupler 67. Path
  • phase shift 15 70 is longer than path 69, whereby a phase shift is introduced between the signal components propagating through paths 69 and 70.
  • the phase shift can also be induced by providing paths 69 and 70 with different refractive indices or widths.
  • 20 paths 69 and 70 can be doped with a rare earth element, the shading on path 69 indicates such doping in that path.
  • the refractive index of the doped path changes when pump power is introduced into the appropriate input path. This causes an input signal introduced at
  • Mach-Zehnder devices become increasingly more sensitive to temperature as the wavelength separation between the peaks of the power output vs. wavelength curve

Landscapes

  • Physics & Mathematics (AREA)
  • Nonlinear Science (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Optical Modulation, Optical Deflection, Nonlinear Optics, Optical Demodulation, Optical Logic Elements (AREA)
  • Keying Circuit Devices (AREA)
  • Oscillators With Electromechanical Resonators (AREA)
  • Transmitters (AREA)
  • Optical Integrated Circuits (AREA)
  • Optical Couplings Of Light Guides (AREA)

Abstract

Commutateur compact monolithique de Mach-Zehnder conçu de telle façon qu'un des trajets de guides d'ondes (69, 70) entre les coupleurs d'entrée et de sortie (67, 68) contient un matériau présentant une non linéarité résonante, ce qui modifie son indice de réfraction quand une puissance de pompage se propage à travers ledit matériau. Chacun des trajets de guides d'ondes (69, 70) possède une constante de propagation différente, ce qui soumet le signal lumineux à un temps de propagation différent dans chaque trajet, quand aucune puissance de pompage se propage à travers le trajet non linéaire en éléments des terres rares. Un signal d'entrée appliqué à l'entrée (71, 72) du commutateur apparaît au niveau d'une première borne de sortie (73, 74), quand la puissance de pompage ne se propage pas à travers le trajet non linéaire et apparaît au niveau d'une deuxième borne de sortie (73, 74), quand la puissance de pompage est appliquée au trajet non linéaire. La commutation s'effectue à des niveaux relativement bas de la puissance de pompage.
EP96916609A 1995-06-09 1996-05-23 Commutateur de mach-zehnder Withdrawn EP0873532A4 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US48909095A 1995-06-09 1995-06-09
US489090 1995-06-09
PCT/US1996/007648 WO1996042027A1 (fr) 1995-06-09 1996-05-23 Commutateur de mach-zehnder

Publications (2)

Publication Number Publication Date
EP0873532A1 true EP0873532A1 (fr) 1998-10-28
EP0873532A4 EP0873532A4 (fr) 1999-12-15

Family

ID=23942367

Family Applications (1)

Application Number Title Priority Date Filing Date
EP96916609A Withdrawn EP0873532A4 (fr) 1995-06-09 1996-05-23 Commutateur de mach-zehnder

Country Status (5)

Country Link
EP (1) EP0873532A4 (fr)
JP (1) JPH11507741A (fr)
AU (1) AU697911B2 (fr)
CA (1) CA2221749A1 (fr)
WO (1) WO1996042027A1 (fr)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5703975A (en) * 1995-06-09 1997-12-30 Corning Incorporated Interferometric switch
EP1091222A3 (fr) * 1996-07-08 2001-05-02 Corning Incorporated Méthode de fabrication d'un interféromètre Mach-Zehnder avec des fibres composites
CA2276489A1 (fr) * 1997-01-02 1998-07-09 The Board Of Trustees Of The Leland Stanford Junior University Commutateur de fibres optiques de type mach-zehnder non lineaire stable
KR100219712B1 (ko) * 1997-02-26 1999-09-01 윤종용 저손실 능동광소자 및 그 제조방법
KR100219714B1 (ko) * 1997-02-26 1999-09-01 윤종용 저손실 광능동소자의 제작방법
US5970185A (en) * 1997-10-31 1999-10-19 Northern Telecom Limited Optical switches, modulators and transmitters
WO2023218578A1 (fr) * 2022-05-11 2023-11-16 日本電信電話株式会社 Commutateur optique

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA2009352C (fr) * 1989-02-07 1995-02-28 Masao Kawachi Elements de raccordement pour guides de lumiere et commutateurs optiques
US5148503A (en) * 1991-05-29 1992-09-15 Crystal Technology, Inc Apparatus and method for linearized cascade coupled integrated optical modulator
GB2264807B (en) * 1992-02-20 1995-10-04 Univ Southampton Optical amplifier
DE4238103A1 (de) * 1992-11-12 1994-05-19 Sel Alcatel Ag Optischer Schalter
US5295205A (en) * 1993-03-29 1994-03-15 Corning Incorporated Environmentally stable monolithic Mach-Zehnder device
US5351325A (en) * 1993-04-29 1994-09-27 Corning Incorporated Narrow band Mach-Zehnder filter

Also Published As

Publication number Publication date
WO1996042027A1 (fr) 1996-12-27
JPH11507741A (ja) 1999-07-06
AU697911B2 (en) 1998-10-22
CA2221749A1 (fr) 1996-12-27
EP0873532A4 (fr) 1999-12-15
AU5929996A (en) 1997-01-09

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