CN110286444B - Reconfigurable micro-ring optical switch based on phase change material - Google Patents
Reconfigurable micro-ring optical switch based on phase change material Download PDFInfo
- Publication number
- CN110286444B CN110286444B CN201910516164.2A CN201910516164A CN110286444B CN 110286444 B CN110286444 B CN 110286444B CN 201910516164 A CN201910516164 A CN 201910516164A CN 110286444 B CN110286444 B CN 110286444B
- Authority
- CN
- China
- Prior art keywords
- waveguide
- micro
- change material
- ring resonator
- phase
- 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.)
- Active
Links
- 230000003287 optical effect Effects 0.000 title claims abstract description 133
- 239000012782 phase change material Substances 0.000 title claims abstract description 125
- 230000008878 coupling Effects 0.000 claims abstract description 60
- 238000010168 coupling process Methods 0.000 claims abstract description 60
- 238000005859 coupling reaction Methods 0.000 claims abstract description 60
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 31
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 31
- 239000010703 silicon Substances 0.000 claims abstract description 31
- 230000001105 regulatory effect Effects 0.000 claims abstract description 16
- 230000008859 change Effects 0.000 claims description 23
- 239000000463 material Substances 0.000 claims description 14
- 238000005253 cladding Methods 0.000 claims description 13
- 230000000694 effects Effects 0.000 claims description 12
- 238000000034 method Methods 0.000 claims description 4
- 230000008033 biological extinction Effects 0.000 abstract description 6
- 238000013461 design Methods 0.000 abstract description 3
- 238000005265 energy consumption Methods 0.000 abstract description 3
- 230000001276 controlling effect Effects 0.000 abstract description 2
- 238000010586 diagram Methods 0.000 description 14
- 230000005540 biological transmission Effects 0.000 description 13
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 6
- 238000003780 insertion Methods 0.000 description 6
- 230000037431 insertion Effects 0.000 description 6
- 238000005452 bending Methods 0.000 description 4
- 238000000151 deposition Methods 0.000 description 4
- 230000001808 coupling effect Effects 0.000 description 3
- 239000013078 crystal Substances 0.000 description 3
- 239000000377 silicon dioxide Substances 0.000 description 3
- 238000004891 communication Methods 0.000 description 2
- 230000002349 favourable effect Effects 0.000 description 2
- 239000012212 insulator Substances 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 235000012239 silicon dioxide Nutrition 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 238000003491 array Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 239000012792 core layer Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000010410 layer Substances 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000002070 nanowire Substances 0.000 description 1
- 230000008569 process Effects 0.000 description 1
Images
Classifications
-
- 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
- G02B6/35—Optical coupling means having switching means
- G02B6/3536—Optical coupling means having switching means involving evanescent coupling variation, e.g. by a moving element such as a membrane which changes the effective refractive index
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Optical Integrated Circuits (AREA)
Abstract
The invention discloses a reconfigurable micro-ring optical switch based on a phase change material. The invention comprises two bus waveguides, a micro-ring resonator and a mixed waveguide carrying phase-change materials; the hybrid waveguide comprises a silicon waveguide and a phase change material arranged on the silicon waveguide, is arranged on the outer side or the inner side of the micro-ring resonator and is arranged into an arc-shaped section which is inosculated with the micro-ring resonator; lateral evanescent wave coupling occurs between the micro-ring resonator and the input/output waveguide and between the micro-ring resonator and the uploading/downloading waveguide, so that optical field resonance is generated in the micro-ring resonator; the micro-ring resonator and the mixed waveguide carrying the phase change material are subjected to lateral evanescent wave coupling and used for regulating and controlling light field resonance in the micro-ring, so that the on-off routing of a light path is realized. The phase change material has the advantages of simple and compact structure, convenient design and high stability, overcomes the technical problem of high loss of the phase change material, reduces crosstalk, improves extinction ratio, can realize self-holding characteristic and has low energy consumption, and is suitable for reconfigurable and tunable wavelength division multiplexing systems.
Description
Technical Field
The invention relates to a planar optical waveguide integrated device, in particular to a reconfigurable micro-ring optical switch based on a phase change material.
Background
It is known that long-distance optical communication has been successful greatly, and many node units in an optical communication network can exchange and route data through optical path transmission, optical interconnection has attracted much attention as a new interconnection mode to overcome the bottleneck problem of the conventional electrical interconnection, since the optical interconnection scheme adopted in V L SI was proposed by j.w. goodman in 1984, optical interconnection research has made a great progress.
In an integrated planar optical waveguide device, optical switches based on a mach-zehnder interferometer (MZI) and a microring resonator (MRR) have been studied in a large amount, and some schemes have been commercialized. Arrays of optical switches of considerable performance have been implemented on integrated platforms by electro-optical or thermo-optical effects. In consideration of the miniaturization and compactness of the device size scale, the basic unit of the micro-ring resonator acting optical switch is often adopted. The traditional optical switch based on the micro-ring resonator changes the mode effective refractive index of the micro-ring waveguide through the electro-optic effect or the thermo-optic effect, so that the resonance peak is translated, the change of the optical power at a specific wavelength is realized, and the effect of switching the state of an optical path is achieved. In this structure, the optical switch needs to continuously consume energy when being maintained in a certain state, for example, the power consumption of the thermo-optical switch is in the milliwatt level; on the other hand, the switching of the optical path state depends on the shift of the resonance peak, which may affect the optical power of the adjacent wavelength signal, increase the crosstalk between the adjacent channels, and is not favorable for the application in the wavelength division multiplexing system.
In recent years, optical switching devices incorporating phase change materials have attracted considerable attention from researchers because they can generate a large refractive index difference and are nonvolatile, and they require only energy to be supplied when the state is changed, and there have been some advances in the past few years in the research of optical switches incorporating phase change materials. For example, the documents Stegmaier, m., rtiios, c., bharscaran, h., Wright, c.d.,&(2017) Nonvolatile all-Optical 1 × 2switch for chip photonic networks advanced Optical Materials,5(1), 1-6. design a method for depositing Ge on a micro-ring in a certain area2Sb2Te5(GST225) has an extinction ratio close to 5 dB. The scheme of utilizing the phase-change material to adjust the resonance state of the micro-ring does not change the position of a resonance peak, so that the channel crosstalk of the optical switch is low, the optical switch is suitable for a wavelength division multiplexing system, and meanwhile, the non-volatility of the phase-change material enables the optical switch to only provide energy when the state is switched, so that the power consumption is reduced. However, the loss of the phase-change material is large, and the direct deposition on the microring introduces large insertion loss, which is not favorable for the subsequent transmission and detection reception of signals, and limits the further practical and commercial application in the field of optical switches.
Disclosure of Invention
In order to solve the problems existing in the background technology, the invention aims to provide a reconfigurable micro-ring optical switch based on a phase change material, a mixed waveguide structure for depositing the phase change material on a silicon waveguide is adopted to generate lateral evanescent wave coupling with a micro-ring, the resonance state of the micro-ring is regulated and controlled to further realize the switching of signal output at different ports, the insertion loss and channel crosstalk are reduced while the high extinction ratio is realized, the reconfigurable micro-ring optical switch is suitable for reconfigurable and tunable wavelength division multiplexing systems, and the low power consumption requirement is met.
The technical scheme adopted by the invention is as follows:
the invention comprises an input and output waveguide of a bus optical signal, an uploading and downloading waveguide of a local optical signal and a micro-ring resonator, wherein the micro-ring resonator is arranged between the input and output waveguide and the uploading and downloading waveguide; the device also comprises a mixed waveguide carrying the phase-change material; the hybrid waveguide comprises a silicon waveguide and a phase change material arranged on the silicon waveguide, the hybrid waveguide is arranged on the outer side or the inner side of the micro-ring resonator, the hybrid waveguide is arranged into an arc-shaped section matched with the micro-ring resonator, and the hybrid waveguide and the micro-ring resonator are of concentric circle structures or non-concentric circle structures; lateral evanescent wave coupling occurs between the micro-ring resonator and the input/output waveguide and between the micro-ring resonator and the uploading/downloading waveguide, so that optical field resonance is generated in the micro-ring resonator; the micro-ring resonator and the mixed waveguide carrying the phase change material are subjected to lateral evanescent wave coupling, and the optical field resonance in the micro-ring resonator is regulated and controlled.
The state of the phase-change material is changed by applying voltage or laser irradiation to the phase-change material in the mixed waveguide to induce an electro-optic effect or a thermo-optic effect, and then the mixed waveguide carrying the phase-change material is regulated and controlled by the state change of the phase-change material; the waveguide height, width, length and curvature radius of the phase-change material are variable, and the waveguide width, length and curvature radius of the silicon waveguide are variable. When the state of the phase-change material is changed, the mode effective refractive index of the mixed waveguide carrying the phase-change material is changed, and the resonance state of an optical field in the micro-ring resonator is changed through lateral evanescent wave coupling, so that the optical field is resonated or not resonated, and an output port of a certain path of wavelength signals is regulated and controlled.
The state change of the two phases of the phase change material adjusts the resonance state of an optical field in the micro-ring resonator through lateral evanescent wave coupling, so that wavelength signals meeting resonance conditions in the micro-ring resonator can be uploaded from a local optical signal to be downloaded to a download end of a download waveguide or output from an output end of a bus optical signal input/output waveguide, and the switching selection of specific wavelength signals is realized.
The mixed waveguide carrying the phase change material has the structure that the phase change material is deposited on the silicon waveguide, and the section of the deposited phase change material is axially symmetrical to the silicon waveguide or deviates to the outer side or the inner side of the central axis of the section of the silicon waveguide.
The phase-change material is VO for example2Or Ge2Sb2Te5(GST225) or Ge2Sb2Se4Te1(GSST), but is not limited thereto.
The input and output waveguide, the uploading and downloading waveguide, the micro-ring resonator and the hybrid waveguide are made of the same upper cladding material, and the input and output waveguide, the uploading and downloading waveguide, the micro-ring resonator and the hybrid waveguide are made of the same lower cladding material.
The upper cladding and the lower cladding are all surrounding cladding media, and are specifically silicon dioxide.
Two ends of the hybrid waveguide are arranged to be of a conical structure or a bending gradual change structure, so that reflection caused by abrupt change of the section of the waveguide when the hybrid waveguide is coupled with the micro-ring resonator can be reduced.
The input and output waveguides and the uploading and downloading waveguides are not parallel to each other and have waveguide intersection, the mixed waveguide carrying the phase-change material can surround a larger angle when being placed on the outer side of the micro-ring resonator, the mixed waveguide carrying the phase-change material is respectively placed on two sides of the outer part of the micro-ring resonator, or the mixed waveguide carrying the phase-change material is placed on both the inner side and the outer side of the micro-ring resonator.
The coupling structures of the micro-ring resonator and the input/output waveguide and the uploading/downloading waveguide are respectively straight waveguide coupling, mutually same-direction bent waveguide coupling or mutually opposite bent waveguide coupling; the distance between the input/output waveguide and the uploading/downloading waveguide and the micro-ring resonator is variable, and the curved waveguide and the micro-ring resonator in the mutually-equidirectional curved waveguide coupling/mutually-reversed curved waveguide coupling structure form a concentric circle structure or a non-concentric circle structure.
The micro-ring resonator comprises a plurality of micro-rings, the micro-rings are longitudinally arranged in a cascade manner between the input/output waveguide and the uploading/downloading waveguide along the extending and arranging direction vertical to the input/output waveguide/uploading/downloading waveguide, and one side of each micro-ring is provided with a mixed waveguide carrying a phase-change material; the structure parameters of the micro-rings are variable, such as radius and waveguide width, the space between the adjacent micro-rings is variable, and the structure parameters of the mixed waveguides are variable, such as waveguide height, width, length and curvature radius.
The micro-ring resonators are transversely arranged in a cascade manner between the input and output waveguides and the uploading and downloading waveguides along the extending and arranging direction parallel to the input and output waveguides/the uploading and downloading waveguides to form an optical switch array, and one side of each micro-ring is provided with a mixed waveguide carrying a phase-change material; the micro-ring resonators in the optical switch array have variable respective structural parameters such as radius and waveguide width, and the hybrid waveguides have variable respective structural parameters such as waveguide height, width, length and radius of curvature.
The input and output waveguides of the bus optical signals, the uploading and downloading waveguides of the local optical signals and the micro-ring resonators are all single-mode waveguides; the mixed waveguide carrying the phase change material is a single-mode waveguide or a multi-mode waveguide.
The invention has the beneficial effects that:
the micro-ring resonator is used as a basic structural unit of the optical switch, and has the advantages of simple and compact structure, convenient design and high stability.
The refractive index change between two phases of the phase-change material used in the invention is large, so that the light field difference of the switch in two states is easier to increase, and the switching efficiency is improved; meanwhile, the phase-change material has non-volatility, can realize self-holding characteristic, only needs to provide energy when the switch state is switched, and is low in energy consumption.
The mixed waveguide carrying the phase change material is placed in the horizontal lateral direction of the micro-ring, the mode of directly depositing the phase change material on the micro-ring is replaced, the light field resonance in the micro-ring is regulated and controlled through the lateral evanescent wave coupling of the mixed waveguide and the micro-ring instead of the direct absorption of the phase change material, the defect of the loss of the light field in the micro-ring caused by the height loss of the phase change material is overcome, the insertion loss and the channel crosstalk of an output port of an optical switch are reduced, the extinction ratio of the switching state is improved, and the phase change material phase change optical switch is suitable for reconfigurable and tunable wavelength division multiplexing systems.
Drawings
Fig. 1 is a schematic structural view of the present invention.
Fig. 2 is a schematic cross-sectional view of a hybrid waveguide carrying a phase change material.
Fig. 3 is a schematic diagram of a tapered structure introduced at both ends of a hybrid waveguide carrying a phase change material.
Fig. 4 is a schematic diagram of introducing a curved graded structure at two ends of a hybrid waveguide carrying a phase change material.
Fig. 5 is a schematic view of a modified structure in which the length of the hybrid waveguide carrying the phase change material is long.
Fig. 6 is a schematic diagram of the structure of the bus waveguide coupled to the micro-ring as a straight waveguide.
Fig. 7 is a schematic diagram of a bus waveguide coupled to a curved waveguide having a homodromous microring.
Fig. 8 is a schematic diagram of a configuration in which a bus waveguide is coupled to a curved waveguide in which the microring is inverted.
Fig. 9 is a schematic diagram of a structure including a plurality of longitudinal cascades of microrings in a microring resonator.
Fig. 10 is a schematic diagram of a structure in which a plurality of microring resonators are laterally cascaded.
Fig. 11 is a schematic structural diagram of an embodiment of the present invention.
FIG. 12 is a diagram of local optical field transmission of the hybrid waveguide carrying phase change material coupled to a microring in an embodiment of the present invention.
FIG. 13 is a graph showing the variation of light intensity with wavelength for two output ports according to the embodiment of the present invention.
In the figure: 1. the optical switch array comprises an input and output waveguide of a bus optical signal, 2 an uploading and downloading waveguide of a local optical signal, 3 a micro-ring resonator, 4 a mixed waveguide carrying a phase change material, 5 a phase change material, 6 a silicon waveguide, 7 a surrounding cladding medium, 8 a conical structure, 9 a curved gradual change structure, 10 a straight waveguide coupling structure, 11 a same-direction curved waveguide coupling structure, 12 a reverse curved waveguide coupling structure, 13 a plurality of micro-rings which are longitudinally arranged in a cascade manner, and 14 an optical switch array which is transversely cascaded by the micro-ring resonator.
Detailed Description
The invention is further illustrated by the following figures and examples.
As shown in fig. 1, the embodiment of the present invention includes an input/output waveguide 1 for a bus optical signal, an upload/download waveguide 2 for a local optical signal, a micro-ring resonator 3, and a hybrid waveguide 4 carrying a phase change material; the micro-ring resonator 3 is arranged between the input and output waveguide 1 and the uploading and downloading waveguide 2, and the hybrid waveguide 4 is arranged at the outer side or the inner side of the micro-ring resonator 3; the input and output waveguide 1 of the bus optical signal, the uploading and downloading waveguide 2 of the local optical signal and the mixed waveguide 4 carrying the phase change material are in lateral evanescent coupling with the micro-ring resonator 3, so that optical path transmission in the whole structure is realized.
As shown in fig. 2, the hybrid waveguide 4 carrying the phase change material includes a silicon waveguide 6 and a phase change material 5 disposed on the silicon waveguide 6, the phase change material 5 is disposed in the middle of the upper surface of the silicon waveguide 6, the silicon waveguide 6 and the phase change material 5 of the hybrid waveguide 4 are both disposed in an arc segment coinciding with the micro-ring resonator 3, and the hybrid waveguide 4 and the micro-ring resonator 3 form a concentric circle structure; lateral evanescent wave coupling occurs between the micro-ring resonator 3 and the input/output waveguide 1 and between the micro-ring resonator and the uploading/downloading waveguide 2, so that optical field resonance is generated in the micro-ring resonator 3; the micro-ring resonator 3 and the mixed waveguide 4 carrying the phase change material are subjected to lateral evanescent wave coupling to regulate and control light field resonance in the micro-ring resonator 3.
The reconfigurable micro-ring optical switch is provided with four ports, wherein the four ports are a first port for inputting a bus optical signal, a second port for outputting the bus optical signal, a third port for uploading a certain path of wavelength signal in a local optical signal and a fourth port for downloading a certain path of wavelength signal in the local optical signal; two ends of an input/output waveguide 1 of the bus optical signal are respectively used as a first port and a second port, and two ends of an upload/download waveguide 2 of the local optical signal are respectively used as a third port and a fourth port.
The input and output of the bus optical signal pass through the same input and output waveguide 1, and the uploading and downloading of the local optical signal pass through the same uploading and downloading waveguide 2; the bus optical signal is input from one side of the input-output waveguide 1 of the bus optical signal, and is output from the other side; through the selection function of the micro-ring resonator 3, a certain path of specific wavelength signal which meets the micro-ring resonance condition and is input at one side of the input and output waveguide 1 of the bus optical signal is subjected to evanescent wave coupling of the micro-ring resonator 3 and is downloaded and output from the same side of the uploading and downloading waveguide 2 of the local optical signal; a certain local path of specific wavelength signal meeting the micro-ring resonance condition is uploaded to the output end of the input/output waveguide 1 of the bus optical signal from the other side of the uploading/downloading waveguide 2 of the local optical signal through evanescent wave coupling of the micro-ring resonator 3.
The state of the phase-change material 5 is changed by applying voltage or laser irradiation to the phase-change material 5 in the hybrid waveguide 4 to cause an electro-optic effect or a thermo-optic effect, and then the hybrid waveguide 4 carrying the phase-change material is regulated and controlled by the state change of the phase-change material 5; when the state of the phase-change material 5 is changed, the mode effective refractive index of the mixed waveguide 4 carrying the phase-change material is changed, and the resonance state of an optical field in the micro-ring resonator 3 is changed through lateral evanescent wave coupling, so that the optical field is resonated or not resonated, and an output port of a certain path of specific wavelength signals is regulated and controlled.
Thus, the on-off state control of a certain wavelength signal in the bus optical signal is realized by the mixed waveguide 4 carrying the phase-change material; a certain path of specific wavelength signals meeting the micro-ring resonance condition input from one end of the input and output waveguide 1 of the bus optical signal are selected to be downloaded and output from the uploading and downloading waveguide 2 of the local optical signal or directly output from the other end of the input and output waveguide 1 of the bus optical signal; meanwhile, a certain path of specific wavelength signals meeting the micro-ring resonance condition in the uploading and downloading waveguides 2 of the local optical signals can be selectively uploaded to the input and output waveguides 1 for output.
As shown in fig. 2, the hybrid waveguide 4 carrying the phase change material has a structure in which the phase change material 5 is deposited on the silicon waveguide 6, and the cross section of the deposited phase change material 5 is axisymmetric to the silicon waveguide 6 or is biased to the outside or inside of the central axis of the cross section of the silicon waveguide 6.
The phase change material-carrying hybrid waveguide 4 is located outside or inside the micro-ring resonator 3 depending on the magnitude of the material refractive index of the phase change material 5, and forms a concentric structure or a non-concentric structure with the micro-ring resonator 3.
The upper cladding materials of the input and output waveguide 1, the uploading and downloading waveguide 2, the micro-ring resonator 3 and the hybrid waveguide 4 are the same, and the lower cladding materials of the input and output waveguide 1, the uploading and downloading waveguide 2, the micro-ring resonator 3 and the hybrid waveguide 4 are the same. Both the upper and lower cladding layers are embodied as surrounding cladding dielectric 7, specifically silica.
As shown in fig. 4, the curved graded structures 9 introduced at two ends of the phase change material-loaded hybrid waveguide 4 are respectively connected to two ends of the phase change material 5 and the silicon waveguide 6 in the phase change material-loaded hybrid waveguide 4, so as to reduce reflection caused by abrupt change of the waveguide cross section when coupled with the micro-ring resonator 3.
The specific waveguide of the phase change material 5 can be a sub-wavelength structure so as to improve the flexibility of the regulation and control of the coupling effect.
As shown in fig. 5, when the length of the phase change material-carrying hybrid waveguide 4 is long, the two bus waveguides 1 and 2 are no longer parallel to each other and cross, or on the basis of keeping the two bus waveguides 1 and 2 parallel, the phase change material-carrying hybrid waveguide 4 is placed at another position where the micro-ring resonator 3 can generate lateral evanescent wave coupling, specifically, the phase change material-carrying hybrid waveguide 4 is placed at both sides or inside and outside of the micro-ring resonator 3.
The coupling structures of the micro-ring resonator 3 and the input/output waveguide 1 and the uploading/downloading waveguide 2 are a straight waveguide coupling 10, a mutually same-direction bent waveguide coupling 11 or a mutually opposite bent waveguide coupling 12; the input/output waveguide 1 and the upload/download waveguide 2 have variable distances from the micro-ring resonator 3, and the curved waveguides and the micro-ring resonator 3 in the structures of the mutually-oriented curved waveguide coupling 11 and the mutually-oriented curved waveguide coupling 12 form a concentric circle structure or a non-concentric circle structure, as shown in fig. 6, 7 and 8.
As shown in fig. 9, the microring resonator 3 includes a plurality of microrings 13, the microrings 13 are arranged in a longitudinal cascade manner between the input/output waveguide 1 and the uploading/downloading waveguide 2 along an extending direction perpendicular to the input/output waveguide 1/uploading/downloading waveguide 2, and one side of each microring is provided with a mixed waveguide 4 carrying a phase change material; the respective structural parameters of the plurality of microrings 13, such as radius, waveguide width, spacing between adjacent microrings, and the respective structural parameters of the plurality of hybrid waveguides 4, such as waveguide height, width, length, and radius of curvature, are variable.
As shown in fig. 10, the microring resonators 3 are arranged in a horizontal cascade between the input/output waveguide 1 and the upload/download waveguide 2 along the extending direction parallel to the input/output waveguide 1/upload/download waveguide 2 to form an optical switch array 14, and one side of each microring is provided with a mixed waveguide 4 carrying a phase change material; the micro-ring resonators 3 in the optical switch array 14 have variable respective structural parameters such as radius and waveguide width, and the hybrid waveguides 4 have variable respective structural parameters such as waveguide height, width, length and curvature radius, so as to realize the selection of uploading and downloading signals at multiple wavelengths in the wavelength division multiplexing system.
The working process and principle of the invention are as follows:
the on-off state control of a certain path of wavelength signal is realized by the mixed waveguide 4 carrying the phase-change material, and the mode effective refractive index of the mixed waveguide 4 carrying the phase-change material is changed by regulating the phase state of the phase-change material 5, so that the coupling effect of the mixed waveguide 4 carrying the phase-change material and the micro-ring resonator 3 can be regulated, and further the optical field resonance in the micro-ring resonator 3 can be regulated, and the optical signal at the specific wavelength satisfying the resonance condition in the micro-ring resonator 3 is output from the output end of the bus optical signal input/output waveguide 1 or the download end of the local optical signal uploading/downloading waveguide 2.
When the phase-change material 5 is in a state of a certain phase, the mode effective refractive index of the phase-change material-carrying hybrid waveguide 4 and the micro-ring resonator 3 meets the phase matching condition of lateral evanescent wave coupling, the optical signal coupled into the micro-ring resonator 3 by the bus optical signal input and output waveguide 1 can be coupled into the phase-change material-carrying hybrid waveguide 4, and the optical field resonance in the micro-ring resonator 3 is destroyed. In this state, the optical signal cannot be coupled into the local optical signal upload/download waveguide 2, but is directly output from the output end of the bus optical signal input/output waveguide 1, the output end of the bus optical signal input/output waveguide 1 is in an "on" state, and the download end of the local optical signal upload/download waveguide 2 is in an "off" state.
When the phase-change material 5 is changed into another phase state, the refractive index of the material is greatly changed, so that the mode effective refractive index of the mixed waveguide 4 carrying the phase-change material is also greatly changed, the phase matching condition of lateral evanescent wave coupling with the micro-ring resonator 3 is no longer met, the optical signal in the micro-ring resonator 3 is not coupled into the mixed waveguide 4 carrying the phase-change material, and the optical signal at the specific wavelength in the micro-ring resonator 3 meeting the resonance condition can generate optical field resonance. Under this state, the specific wavelength optical signal input in the bus optical signal input/output waveguide 1 is subjected to the resonance selection action of the micro-ring resonator 3, and is output from the download end of the local optical signal upload download waveguide 2, and becomes an "on" state, and the output end of the bus optical signal input/output waveguide 1 becomes an "off" state, thereby realizing the function of optical path switch routing.
The specific embodiment of the invention is as follows:
in the embodiment, a silicon nanowire optical waveguide based on a silicon-on-insulator (SOI) material is selected, a core layer material is silicon, the thickness is 220nm, the refractive index is 3.4744, a surrounding cladding material is silicon dioxide, the refractive index is 1.444, the waveband range is considered to be 1500nm to 1600nm, and the phase change of the phase change material is regulated and controlled through a thermo-optic effect of applying voltage to an electrode.
The coupling structure of the micro-ring resonator 3 and the two bus waveguides 1 and 2 may adopt a straight waveguide coupling 10, a same-direction curved waveguide coupling 11 or a reverse curved waveguide coupling 12, in this example, the same-direction curved waveguide coupling 11 is adopted, and the coupling structure is a concentric circle structure. The micro-ring resonator 3 and the hybrid waveguide 4 carrying the phase change material are also of concentric structure.
In the mixed waveguide 4 carrying the phase change material, the section of the waveguide of the phase change material 5 is axisymmetric with the silicon waveguide 6 below the waveguide, and the waveguide is of a concentric circle structure; the waveguide of the phase-change material 5 is of a sub-wavelength structure so as to improve the flexibility of regulating and controlling the coupling effect; two ends of the hybrid waveguide 4 carrying the phase-change material are connected with two tapered waveguide structures 8 so as to reduce reflection caused by abrupt change of the waveguide section when the hybrid waveguide is coupled with the micro-ring resonator 3; the hybrid waveguide 4 carrying the phase change material is long, and the two bus waveguides 1 and 2 are arranged to intersect vertically.
In the device structure of the embodiment, the waveguide width of two bus waveguides 1 and 2 is taken as WSi450nm, the waveguide width satisfies the single-mode transmission condition. The radius of the micro-ring resonator 3 is RWThe waveguide width of the microring resonator 3 is W5 μmring450 nm. In the coupling structure of the two bus waveguides 1 and 2 and the micro-ring resonator 3, the waveguide distance of the coupling region is WGThe bending radius of the coupling region of the two bus waveguides 1 and 2 is 240nmS5.69 μm. The two bus waveguides 1 and 2 in the coupling region have proper bending angles, so that the amplitude through coupling coefficient of the bus optical signal input and output waveguide 1 is 0.981, and the amplitude through coupling coefficient of the local optical signal upload and download waveguide 2 is 0.985.
The phase-change material 5 is Ge2Sb2Te5(GST225) having a refractive index of 4.21+0.0567i in an amorphous state and a refractive index of 7.00+1.0871i in a crystalline state at 1550 nm. When the phase-change material 5 is in a crystal state, the phase-change material-carrying hybrid waveguide 4 and the micro-ring resonator 3 meet the phase matching condition of lateral evanescent wave coupling, and the waveguide width of the silicon waveguide 6 below the hybrid waveguide 4 is WS320nm, waveguide width of phase change material 5 waveguide is WP280nm and a waveguide height HPThe waveguide width and height satisfy the single-mode transmission condition at 30 nm. The waveguide distance between the phase change material-carrying hybrid waveguide 4 and the microring resonator 3 is WG240nm with a radius of curvature RP5.625 μm, and the ring bending angle Φ is 120 °. The phase change material 5 waveguide is of a sub-wavelength structure, and the sub-wavelength period is TP250nm, duty cycle 0.5. In the taper structure 8 of the phase change material-carrying hybrid waveguide 4, the taper structure of the phase change material 5 waveguideLength tp0.6 μm, the length of the tapered structure of the silicon waveguide 6 is ts0.8 μm. The height of all waveguide structures with the waveguide material of silicon is HSi220nm, consistent with the thickness of the core silicon of silicon-on-insulator (SOI) material.
Fig. 12 shows a local optical field transmission diagram of the coupling of the hybrid waveguide 4 carrying the phase change material and the micro-ring resonator 3, in which the transmission mode is a transverse electric TE fundamental mode and the wavelength is 1550nm, and the simulation is performed by using 3D-FDTD. In the local optical field transmission diagram, light enters the waveguide coupling structure from the left side of the annular waveguide upwards, and is output from the lower side of the annular waveguide leftwards after the transmission direction is changed by 270 degrees. Phase change material Ge in graph a2Sb2Te5The phase-change material-carrying hybrid waveguide 4 and the micro-ring resonator 3 are in a crystal state, the phase matching condition of lateral evanescent wave coupling is met, as part of an optical field in the annular waveguide is coupled into the hybrid waveguide 4, the optical field loss of the annular waveguide is large, the optical field resonance equivalent to that in the micro-ring resonator 3 is destroyed, an optical signal in the bus waveguide 1 is directly output from the output end of the bus waveguide, and no light is output from the download end of the local waveguide 2; phase change material Ge in graph b2Sb2Te5The phase-change material-carrying hybrid waveguide 4 and the micro-ring resonator 3 do not meet the phase matching condition of lateral evanescent wave coupling any more at the time of being in an amorphous state, and as can be seen from an optical field transmission diagram, the phase-change material-carrying hybrid waveguide 4 and the micro-ring resonator 3 are weakly coupled, and after a coupling distance of 120 degrees, an optical field is re-coupled back to the ring waveguide, and because of Ge2Sb2Te5The loss is small when the waveguide is in an amorphous state, the transmission loss coupled into the hybrid waveguide 4 is negligible, and equivalently, the optical field resonance in the micro-ring resonator 3 is not affected, and a specific wavelength signal which is input from the bus waveguide 1 and meets the resonance condition of the micro-ring resonator 3 can be output from the download terminal of the local waveguide 2 and is not output from the bus waveguide 1.
FIG. 13 is a schematic diagram showing the variation of the light intensity of the output end of the bus waveguide 1 and the download end of the local waveguide 2 with the wavelength, which is obtained by the calculation of the 3D-FDTD simulation local coupling characteristic and the transmission matrix method, where "Through" in the diagram is the output end of the bus waveguide 1 and "Drop" is the local waveguide2, a downloading end. Phase change material Ge in graph a2Sb2Te5The optical field resonance in the micro-ring resonator 3 is destroyed in a crystal state, corresponding to the condition that the output end of the bus waveguide 1 is in an 'on' state, the download end of the local waveguide 2 is in an 'off' state, and the insertion loss of an optical signal at a working wavelength is less than 1 dB; phase change material Ge in graph b2Sb2Te5The optical field resonance in the micro-ring resonator 3 is not affected in an amorphous state, the load end of the local waveguide 2 is in an 'on' state, the output end of the bus waveguide 1 is in an 'off' state, and the insertion loss of an optical signal at a working wavelength is less than 2 dB; as can be seen from fig. a and b, when the switch states are switched, the extinction ratios of the two ports are both greater than 20dB, and the switch routing of the optical signal can be realized.
Therefore, the waveguide designed by the invention has the advantages of simple and compact structure and high stability, overcomes the technical problem of high loss of the phase-change material, reduces the insertion loss and the channel crosstalk, improves the extinction ratio of the switching state, can realize the self-holding characteristic, has low energy consumption, and obtains remarkable technical effects.
The above-described embodiments are intended to illustrate rather than to limit the invention, and any modifications and variations of the present invention are within the spirit of the invention and the scope of the appended claims.
Claims (7)
1. A reconfigurable micro-ring optical switch based on phase change materials comprises an input and output waveguide (1) of a bus optical signal, an uploading and downloading waveguide (2) of a local optical signal and a micro-ring resonator (3), wherein the micro-ring resonator (3) is arranged between the input and output waveguide (1) and the uploading and downloading waveguide (2); the method is characterized in that: the device also comprises a mixed waveguide (4) carrying the phase-change material; the hybrid waveguide (4) comprises a silicon waveguide (6) and phase change materials (5) arranged on the silicon waveguide (6), the hybrid waveguide (4) is arranged on the outer side or the inner side of the micro-ring resonator (3) at intervals, and the hybrid waveguide (4) is arranged into an arc-shaped section which is matched with the micro-ring resonator (3); lateral evanescent wave coupling occurs between the micro-ring resonator (3) and the input/output waveguide (1) and between the micro-ring resonator and the uploading/downloading waveguide (2), so that optical field resonance is generated in the micro-ring resonator (3); the micro-ring resonator (3) and the mixed waveguide (4) carrying the phase-change material are subjected to lateral evanescent wave coupling, and the optical field resonance in the micro-ring resonator (3) is regulated and controlled;
the state of the phase-change material (5) is changed by applying voltage or laser irradiation to the phase-change material (5) in the hybrid waveguide (4) to induce an electro-optic effect or a thermo-optic effect, and then the hybrid waveguide (4) carrying the phase-change material is regulated and controlled by the state change of the phase-change material (5); when the state of the phase-change material (5) is changed, the mode effective refractive index of the mixed waveguide (4) carrying the phase-change material is changed, and the resonance state of an optical field in the micro-ring resonator (3) is changed through lateral evanescent wave coupling, so that the optical field is resonated or not resonated, and an output port of a certain path of wavelength signal is regulated and controlled;
the structure of the mixed waveguide (4) carrying the phase change material is that the phase change material (5) is deposited on the silicon waveguide (6), and the section of the deposited phase change material (5) is axisymmetric with the silicon waveguide (6) or deviates to the outer side or the inner side of the central axis of the section of the silicon waveguide (6).
2. The reconfigurable micro-ring optical switch based on the phase change material as claimed in claim 1, wherein: the input and output waveguide (1), the uploading and downloading waveguide (2), the micro-ring resonator (3) and the hybrid waveguide (4) are made of the same upper cladding material, and the input and output waveguide (1), the uploading and downloading waveguide (2), the micro-ring resonator (3) and the hybrid waveguide (4) are made of the same lower cladding material.
3. The reconfigurable micro-ring optical switch based on the phase change material as claimed in claim 1, wherein: two ends of the hybrid waveguide (4) are provided with a conical structure (8) or a curved gradual change structure (9), so that reflection caused by abrupt change of the waveguide section when the hybrid waveguide is coupled with the micro-ring resonator (3) can be reduced.
4. The reconfigurable micro-ring optical switch based on the phase change material as claimed in claim 1, wherein: the input and output waveguides (1) and the uploading and downloading waveguides (2) are not parallel to each other and have waveguide intersection, and the two sides outside the micro-ring resonator (3) are respectively provided with the mixed waveguides (4) carrying the phase-change materials, or the two sides inside and outside the micro-ring resonator (3) are respectively provided with the mixed waveguides (4) carrying the phase-change materials.
5. The reconfigurable micro-ring optical switch based on the phase change material as claimed in claim 1, wherein: the coupling structures of the micro-ring resonator (3) and the input/output waveguide (1) and the uploading/downloading waveguide (2) are a straight waveguide coupling (10), a mutually same-direction bent waveguide coupling (11) or a mutually opposite bent waveguide coupling (12); the distance between the input/output waveguide (1) and the uploading/downloading waveguide (2) and the micro-ring resonator (3) is variable, and the curved waveguide and the micro-ring resonator (3) form a concentric circle structure or a non-concentric circle structure in the structures of mutually-equidirectional curved waveguide coupling (11)/mutually-reversed curved waveguide coupling (12).
6. The reconfigurable micro-ring optical switch based on the phase change material as claimed in claim 1, wherein: the micro-ring resonator (3) comprises a plurality of micro-rings (13), the micro-rings (13) are arranged between the input and output waveguides (1) and the uploading and downloading waveguides (2) in a longitudinal cascade mode along the extending and arranging direction perpendicular to the input and output waveguides (1) and the uploading and downloading waveguides (2), and one side of each micro-ring is provided with a mixed waveguide (4) carrying phase-change materials.
7. The reconfigurable micro-ring optical switch based on the phase change material as claimed in claim 1, wherein: the micro-ring resonators (3) are arranged between the input and output waveguides (1) and the uploading and downloading waveguides (2) in a transverse cascade mode along the extending arrangement direction parallel to the input and output waveguides (1) and the uploading and downloading waveguides (2) to form an optical switch array (14), and one side of each micro-ring is provided with a mixed waveguide (4) carrying phase-change materials.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910516164.2A CN110286444B (en) | 2019-06-14 | 2019-06-14 | Reconfigurable micro-ring optical switch based on phase change material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910516164.2A CN110286444B (en) | 2019-06-14 | 2019-06-14 | Reconfigurable micro-ring optical switch based on phase change material |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110286444A CN110286444A (en) | 2019-09-27 |
| CN110286444B true CN110286444B (en) | 2020-07-14 |
Family
ID=68004995
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910516164.2A Active CN110286444B (en) | 2019-06-14 | 2019-06-14 | Reconfigurable micro-ring optical switch based on phase change material |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110286444B (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112462469A (en) * | 2020-12-15 | 2021-03-09 | 中国科学院上海微系统与信息技术研究所 | Silicon-based Mach-Zehnder interferometer based on Y-branch symmetric structure |
| CN113267907A (en) * | 2021-05-14 | 2021-08-17 | 北京工业大学 | Based on phase change material GemSbnTekGraphene auxiliary driving micro-ring optical switch |
| CN113777714A (en) * | 2021-09-30 | 2021-12-10 | 深圳中科天鹰科技有限公司 | Tunable optical switch, optical network node and optical network |
| CN114137745A (en) * | 2021-12-02 | 2022-03-04 | 程唐盛 | Antimony diselenide silicon-based electric dimming switch, optical switch array and chip |
| CN113900285B (en) * | 2021-12-08 | 2022-04-05 | 杭州芯耘光电科技有限公司 | Technology insensitive modulator |
| CN114488651B (en) * | 2022-01-04 | 2022-12-27 | 重庆邮电大学 | Photon digital-to-analog converter based on micro-ring array and GST (GST) and regulation and control method |
| CN114859575B (en) * | 2022-03-28 | 2024-09-20 | 武汉大学 | Adjustable micro-ring optical communication filter based on inverse piezoelectric effect |
| CN116300242B (en) * | 2023-02-28 | 2024-02-06 | 中国人民解放军国防科技大学 | Micro-ring optical waveguide switch based on low-loss phase change material and preparation method thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6925232B2 (en) * | 2003-05-30 | 2005-08-02 | Lucent Technologies, Inc. | High speed thermo-optic phase shifter and devices comprising same |
| CN101833220A (en) * | 2010-04-20 | 2010-09-15 | 浙江大学 | Self-sustaining waveguide optical switch assisted by phase-change material |
| JP5632436B2 (en) * | 2012-10-02 | 2014-11-26 | 日本電信電話株式会社 | Optical wavelength filter |
| CN106324865A (en) * | 2016-08-19 | 2017-01-11 | 上海交通大学 | Phase change material-based three-dimensional integrated optical switch |
| CN108761689A (en) * | 2018-07-02 | 2018-11-06 | 苏州大成瑞丰通信科技有限公司 | A kind of shock resistance optical cable |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5691033B2 (en) * | 2009-12-25 | 2015-04-01 | 学校法人慶應義塾 | Waveguide type optical gate switch |
| CN101866066A (en) * | 2010-05-28 | 2010-10-20 | 浙江大学 | Phase change material-aid micro ring-based optical waveguide switch |
| CN101866065A (en) * | 2010-05-28 | 2010-10-20 | 浙江大学 | Phase change material-aid self-supporting light-controlled optical waveguide switch |
| CN106054317B (en) * | 2016-06-03 | 2019-11-15 | 浙江大学 | A kind of micro-loop filter of the polarization insensitive based on silicon nanowires waveguide |
| WO2018049345A2 (en) * | 2016-09-09 | 2018-03-15 | The Regents Of The University Of California | Silicon-photonics-based optical switch with low polarization sensitivity |
| CN107959541B (en) * | 2016-10-14 | 2019-08-06 | 华为技术有限公司 | The control method and device of micro-ring resonator |
| CN106970443B (en) * | 2017-04-14 | 2019-08-06 | 浙江大学 | A kind of multichannel dual-polarization mode multiplexing-demultiplexer |
| CN108873178A (en) * | 2018-07-02 | 2018-11-23 | 浙江大学 | Based on the switching of the wavelength of micro-ring resonator and Mach-Zehnder modulators without interruption optical router |
-
2019
- 2019-06-14 CN CN201910516164.2A patent/CN110286444B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6925232B2 (en) * | 2003-05-30 | 2005-08-02 | Lucent Technologies, Inc. | High speed thermo-optic phase shifter and devices comprising same |
| CN101833220A (en) * | 2010-04-20 | 2010-09-15 | 浙江大学 | Self-sustaining waveguide optical switch assisted by phase-change material |
| JP5632436B2 (en) * | 2012-10-02 | 2014-11-26 | 日本電信電話株式会社 | Optical wavelength filter |
| CN106324865A (en) * | 2016-08-19 | 2017-01-11 | 上海交通大学 | Phase change material-based three-dimensional integrated optical switch |
| CN108761689A (en) * | 2018-07-02 | 2018-11-06 | 苏州大成瑞丰通信科技有限公司 | A kind of shock resistance optical cable |
Non-Patent Citations (2)
| Title |
|---|
| Low Crosstalk Design of an Optical Matrix Switch Using Phase-Change Material;Takumi Moriyama等;《Advanced Photonics Congress》;20130731;全文 * |
| 集成光开关发展现状及关键技术;周林杰等;《光通信研究》;20190228(第211期);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110286444A (en) | 2019-09-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110286444B (en) | Reconfigurable micro-ring optical switch based on phase change material | |
| KR100888299B1 (en) | Optical switch | |
| US5970186A (en) | Hybrid digital electro-optic switch | |
| US7529455B2 (en) | Optical integrated device and optical control device | |
| Memon et al. | Recent advances in mode converters for a mode division multiplex transmission system | |
| CN114326164A (en) | 2X 2 optical waveguide switch based on phase change material and preparation method thereof | |
| CN112596282B (en) | Broadband adjustable splitting ratio polarization rotation beam splitter based on SOI | |
| CN114721176A (en) | Polarization controller based on-chip mode conversion | |
| CN217181269U (en) | 2X 2 optical waveguide switch based on phase change material | |
| CN110737052A (en) | reconfigurable arbitrary optical mode exchanger based on micro-ring resonator | |
| CN111399125A (en) | Adjustable optical delay line of silicon-based coupling waveguide and adjustable optical delay method | |
| US5917974A (en) | Method and apparatus for implementing coupled guiding structures with apodized interaction | |
| WO2001023955A2 (en) | A nanophotonic mach-zehnder interferometer switch and filter | |
| CN112904479B (en) | Optical switch based on reverse Fano coupling micro-ring | |
| Soref | Phase-change materials for Group-IV electro-optical switching and modulation | |
| CN220473739U (en) | Optical switch device | |
| CN221746336U (en) | 4X 4 array optical waveguide switch | |
| CN218122296U (en) | Multi-mode switching 1X 3 optical switch | |
| Su et al. | Ultra Broadband Tunable Power Splitter Based on Sb 2 Se 3-Assisted Y-Junction | |
| CN221746337U (en) | Optical waveguide switch of 6 x 6 array | |
| CN110174781B (en) | Micro-ring electro-optical switch array device with net structure | |
| Soref | Phase-change materials for electro-optical switching in the near-and mid-infrared | |
| CN115509032A (en) | Nonvolatile silicon-based optical switch with phase-change material auxiliary micro-ring structure | |
| Osgood jr et al. | Integrated Optical Switches | |
| CN116027482A (en) | Multimode optical path state switching unit and multimode optical switch |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |