CN113658613A - Controllable optical storage device and method based on photonic crystal dynamic microcavity - Google Patents
Controllable optical storage device and method based on photonic crystal dynamic microcavity Download PDFInfo
- Publication number
- CN113658613A CN113658613A CN202110774015.3A CN202110774015A CN113658613A CN 113658613 A CN113658613 A CN 113658613A CN 202110774015 A CN202110774015 A CN 202110774015A CN 113658613 A CN113658613 A CN 113658613A
- Authority
- CN
- China
- Prior art keywords
- photonic crystal
- refractive index
- dynamic
- signal light
- optical
- 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.)
- Granted
Links
Images
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
- G11B7/2403—Layers; Shape, structure or physical properties thereof
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
- G11B7/2403—Layers; Shape, structure or physical properties thereof
- G11B7/24062—Reflective layers
Landscapes
- Optical Modulation, Optical Deflection, Nonlinear Optics, Optical Demodulation, Optical Logic Elements (AREA)
Abstract
The invention discloses an optical storage device and method based on a photonic crystal dynamic microcavity, wherein when pulse signal light is transmitted through a preset capture region along a photonic crystal waveguide, optical pumping is simultaneously carried out on refractive index dynamic modulation regions at two ends of the capture region, so that the refractive indexes of the modulation regions at the two ends are instantaneously reduced to form two optical barriers, and the pulse signal light is captured in the photonic crystal dynamic microcavity between the two optical barriers to realize optical storage. When the pulse signal light needs to be released at a certain moment in storage for a certain time, the optical pumping is stopped at any one of the dynamic refractive index modulation regions at the two ends of the capture region at an instant, so that the optical potential barrier at the position disappears and a release channel is formed, and the stored pulse signal light is rapidly released from the channel. The invention also discloses an optical storage device based on the photonic crystal dynamic microcavity. The invention can actively capture the pulse signal light freely transmitted along the photonic crystal waveguide and release the pulse signal light along a given direction.
Description
Technical Field
The invention belongs to the technical field of photonic crystals, and particularly relates to a controllable optical storage device and a controllable optical storage method based on a photonic crystal dynamic microcavity.
Background
The controllable storage and release of light is an important and basic problem in all-optical information processing, and has a very wide application prospect in the fields of all-optical communication, quantum computation, optical path integration and the like.
In order to realize optical storage, it is critical to slow down or even stop the speed of light in the optical transmission medium. In recent years, with the development of micro-nano photonic technology, people have realized slow light with controllable light speed in nonlinear optical fiber and photonic crystal waveguide. The former is mainly realized by generating strong dispersion at the nonlinear gain of the optical fiber through Raman scattering and Brillouin scattering; the latter utilizes the band gap edge dispersion effect of the artificial periodic structure dielectric waveguide. Essentially, these methods regulate the speed of light by generating strong dispersion in the waveguide through specific physical mechanisms, but this easily causes distortion and distortion of the optical signal transmission, and the delay time is usually limited by the length of the transmission medium. In contrast, the high-Q microcavity can localize light in a small space of micro-nano size for a long time without the aid of waveguide dispersion, and thus has natural advantages in chip-scale optical storage. However, high-Q microcavities face a fundamental difficulty: on one hand, the higher the Q value of the microcavity is, the longer the storage life of photons in the microcavity is; on the other hand, however, since the high-Q microcavity has a narrow cavity mode line width, the bandwidth of the pulsed signal light allowed to be coupled into the microcavity is necessarily narrow, and the signal light enters and leaves the high-Q microcavity at a very slow speed (inversely proportional to the Q value), which is obviously disadvantageous for the requirement of high-speed, broadband optical signal processing.
The key to solve the above problems is dynamic Q adjustment: firstly, the microcavity is adjusted to a state with a lower Q value so as to enable pulse signal light with a larger bandwidth to be rapidly coupled into the microcavity from the waveguide, and the microcavity is in an 'on state' at the moment; then, after the pulse signal light completely enters the microcavity, the microcavity is quickly adjusted to an ultrahigh Q value, so that the captured signal light hardly overflows from the microcavity, and the microcavity is in a closed state at the moment, so that the light energy is localized in the cavity for a long time, and the long-time light storage is obtained; when release is required, the microcavity is again tuned to a low-Q state, and the stored signal light can be rapidly coupled from the microcavity into the exit waveguide. However, it is quite difficult to realize large amplitude dynamic Q-switching for micro-cavities, and few approaches are currently available, mainly by introducing a mirror at one side of the photonic crystal waveguide and controlling the destructive or constructive interference between incident light and reflected light by means of precise ultrafast phase modulation, so as to switch the micro-cavity between a "closed state" and an "open state", or by performing adiabatic wavelength conversion on the resonant wavelengths of multiple coupled micro-cavities simultaneously to generate an electromagnetic induction-like transparent effect. The dynamic Q-switching modes are based on the interference effect of phase modulation or the electromagnetic induction transparent effect of multi-microcavity resonant frequency modulation, the related technologies are very complex, the requirements on experimental conditions are very strict, and the application of the dynamic Q-switching modes is limited. Therefore, it is important and critical to discuss a simpler and more efficient method for implementing controllable optical storage.
Disclosure of Invention
In order to overcome the above disadvantages and shortcomings of the prior art, the present invention provides a controllable optical storage device based on a photonic crystal dynamic microcavity, which has a simple structure and is easy to implement and integrate.
Another objective of the present invention is to provide a controllable optical storage method based on a photonic crystal dynamic microcavity, which can perform instantaneous capture and efficient storage on signal light freely transmitted in a photonic crystal waveguide, and quickly release the signal light at any desired time.
In order to achieve the purpose, the invention adopts the following technical scheme:
the invention provides a controllable optical storage device based on a photonic crystal dynamic microcavity, which comprises a wavelength tunable pulse laser, a power tunable pulse laser, a variable optical attenuator, an optical fiber coupler, a polarization controller, a first lens optical fiber, a second lens optical fiber, a first optical switch, a second optical switch, a first micro lens, a second micro lens and a photonic crystal waveguide structure, wherein the first lens optical fiber is arranged on the optical fiber coupler; the photonic crystal waveguide structure comprises a photonic crystal waveguide, a first refractive index dynamic modulation area, a second refractive index dynamic modulation area and a pulse signal light capture area, wherein the first refractive index dynamic modulation area, the second refractive index dynamic modulation area and the pulse signal light capture area are defined on the photonic crystal waveguide, and the photonic crystal waveguide is formed by removing 1 whole line of air holes from the center of a photonic crystal along the x direction; the first refractive index dynamic modulation region, the second refractive index dynamic modulation region and the pulse signal light capture region form a photonic crystal dynamic microcavity;
the signal light emitted by the wavelength tunable pulse laser passes through the variable optical attenuator, the polarization controller and the first lens fiber and then is emitted into the photonic crystal waveguide and enters the pulse signal light capturing area; a signal emitted by the power-adjustable pulse laser is divided into two paths of light after passing through the optical fiber coupler, one path of light pumps a first dynamic refractive index modulation region on the photonic crystal waveguide after passing through the first optical switch and the first micro lens, and the other path of light pumps a second dynamic refractive index modulation region on the photonic crystal waveguide after passing through the second optical switch and the second micro lens in sequence;
the wavelength tunable pulse laser is used for providing incident signal light; the power-adjustable pulse laser is used for optically pumping the dynamic modulation region of the refractive index of the photonic crystal waveguide; the optical switch is used for switching on or off the optical pump for the refractive index dynamic modulation region of the photonic crystal waveguide.
As a preferred technical solution, the photonic crystal waveguide structure forms a triangular lattice in a silicon material flat plate by circular air holes; the diameter of the air hole is 0.524a, wherein a is the lattice constant of the photonic crystal; the thickness of the silicon material flat plate is 0.5 a; the first refractive index dynamic modulation region and the second refractive index dynamic modulation region are formed by two identical rectangular regions on the photonic crystal waveguide, the length and the width of each rectangular region are 6a and 4a respectively, and the center distance of the two rectangular regions is 10a to 20 a; the pulse signal light capture region is located between the first refractive index dynamic modulation region and the second refractive index dynamic modulation region.
As a preferable technical solution, the resonant frequency of the photonic crystal dynamic microcavity is controlled by adjusting the center distance between the first refractive index modulation region and the second refractive index modulation region; the center frequency of incident pulse signal light generated by the wavelength tunable pulse laser is the same as the resonance frequency of the photonic crystal dynamic microcavity.
As a preferable technical scheme, the working wavelength of the wavelength tunable pulse laser is continuously adjustable from 1500nm to 1700nm, the tuning precision is 1MHz, the pulse width is 10ps, and the repetition frequency is 350 MHz.
Preferably, the center wavelength of the power tunable pulse laser is λ ═ (415 ± 2) nm, the pulse width is 1.5ps, and the repetition frequency is 75 MHz.
Preferably, the optical fiber coupler is a 50:50 optical fiber coupler.
The invention also provides an optical storage method of the optical storage device based on the photonic crystal dynamic microcavity, which comprises the following steps:
s1, presetting a pulse signal light capturing area on the photonic crystal waveguide, wherein a first refractive index dynamic modulation area and a second refractive index dynamic modulation area are arranged at two ends of the area; adjusting the center distance between the first refractive index dynamic modulation region and the second refractive index dynamic modulation region, so that the resonance wavelength of the photonic crystal dynamic microcavity formed when the refractive indexes are dynamically modulated is the center wavelength of the pulse signal light;
s2, starting a wavelength tunable pulse laser, and tuning the central wavelength of the pulse laser to the resonance wavelength of the photonic crystal dynamic microcavity; pulse signal light emitted by the tunable pulse laser is incident from the left end of the photonic crystal waveguide and is transmitted along the photonic crystal waveguide;
s3, when the pulse signal light passes through a preset capture area, instantly starting the power-adjustable pulse laser, and simultaneously optically pumping a first refractive index dynamic modulation area and a second refractive index dynamic modulation area at two ends of the capture area, so that the refractive indexes of the first refractive index dynamic modulation area and the second refractive index dynamic modulation area are instantly reduced to form two optical barriers, and capturing the pulse signal light between the two optical barriers to realize optical storage;
and S4, when the pulse signal light needs to be released at a certain moment in storage for a certain time, stopping optical pumping for any one of the dynamic refractive index modulation regions at two ends of the capture region by closing the optical switch, so that the optical barrier at the position disappears and a release channel is formed, and the stored pulse signal light is rapidly released from the channel along a given direction.
As a preferable technical solution, in step S1, the center distance between the first refractive index dynamic modulation region and the second refractive index dynamic modulation region is set to be 10a to 20a, so that the resonance wavelength of the photonic crystal dynamic microcavity formed when the refractive index is dynamically modulated is located in the interval of 1660-.
As a preferred technical solution, in step S2, signal light emitted by the wavelength tunable pulse laser is focused by the first lens fiber and then emitted into the photonic crystal waveguide along the two-dimensional photonic crystal plane, and timing is started; because the power adjustable pulse laser is not started temporarily and the light barrier is not formed yet, the incident pulse signal light is transmitted freely along the photonic crystal waveguide.
As a preferred technical solution, in step S3, a laser beam emitted by the wavelength tunable pulse laser is split into two paths of light by the optical fiber splitting coupler, where one path of light sequentially passes through the first optical switch and the first microlens, and the other path of light sequentially passes through the second optical switch and the second microlens, and then the first dynamic refractive index modulation region and the second dynamic refractive index modulation region at both ends of the pulse signal light capture region are optically pumped simultaneously.
Compared with the prior art, the invention has the following advantages and beneficial effects:
(1) the existing optical storage technology based on the microcavity needs to dynamically adjust Q to the microcavity, mainly based on the interference effect of phase modulation or the similar electromagnetic induction transparent effect of multi-microcavity resonant frequency modulation, and the related technologies are very complex and have very strict requirements on experimental conditions. The invention can efficiently capture, store and release the pulse signal light freely transmitted along the photonic crystal waveguide without phase modulation and the quasi-electromagnetic induction transparent effect based on multiple microcavities and only dynamically modulate the local refractive index of the photonic crystal waveguide through pump illumination, and has simple structure and easy realization and integration.
(2) In the existing optical storage technology based on the microcavity, because the position and the resonant frequency of the microcavity are fixed after processing and forming, the coupling of the pulse signal light into the microcavity with a high Q value is passive and extremely slow, and the allowed working bandwidth of the pulse signal light is extremely narrow, so that the optical storage technology is limited by the product of storage time and working bandwidth. The photonic crystal dynamic microcavity provided by the invention is formed by dynamically modulating the local refractive index of the photonic crystal waveguide through the external pump light, so that the photonic crystal dynamic microcavity can be generated at any required position and time of the photonic crystal waveguide, and the resonant frequency of the photonic crystal dynamic microcavity can be adjusted by changing the central distance of the refractive index dynamic modulation regions at the two ends of the dynamic microcavity. Compared with the traditional fixed microcavity, the dynamic high-Q-value microcavity has higher flexibility and plasticity and a simple manufacturing process. Therefore, the photonic crystal dynamic microcavity is used for capturing the pulse signal light freely transmitted on the photonic crystal waveguide actively and extremely fast, and the incident pulse signal light is allowed to have larger working bandwidth, so that the constraint of the contradiction relationship between storage time and working bandwidth can be broken through.
(3) The existing optical storage technology based on the microcavity has very strict requirements on the variation of the refractive index no matter based on the phase modulation interference effect or based on the multi-microcavity resonant frequency modulation similar electromagnetic induction transparent effect, and the variation of the refractive index is slightly larger or smaller, which can cause great influence on the optical storage effect. In the optical storage technology based on the photonic crystal dynamic microcavity, the photonic crystal dynamic microcavity relies on the optical potential barrier formed by two independent refractive index modulation regions, and the effect of the photonic crystal dynamic microcavity is equivalent to that of two perfect reflectors. Therefore, even if the area of the refractive index modulation region and the refractive index modulation amplitude are greatly changed, the reflection effect of the optical barrier cannot be influenced, so that the photonic crystal dynamic microcavity still keeps an ultrahigh Q value, high-quality optical storage is realized, and the tolerance on the change amount of the refractive index on the photonic crystal waveguide is high.
(4) In the existing optical storage technology based on the microcavity, when the stored signal light is released, the signal light is released simultaneously along the front and back directions of the waveguide, but cannot be released only along a specified direction, so the release direction of the light is uncontrollable. In the optical storage technology based on the photonic crystal dynamic microcavity, when the pulse signal light needs to be released at a certain moment in storage for a certain time, only any one of the dynamic refractive index modulation regions at the two ends of the capture region needs to be stopped from being optically pumped instantly, so that the optical barrier at the position disappears and a release channel is formed, and the stored pulse signal light is rapidly released from the channel, and therefore the release direction is completely controllable.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
FIG. 1 is a schematic diagram of an optical storage device based on photonic crystal dynamic microcavity according to an embodiment of the present invention.
FIG. 2 is a schematic diagram of a photonic crystal waveguide structure and a dynamic refractive index modulation region according to an embodiment of the present invention.
Fig. 3(a) -3 (h) are field distribution evolution diagrams of active capture and storage of freely transmitted pulse signal light by utilizing a photonic crystal dynamic microcavity according to an embodiment of the present invention.
Fig. 4(a) -4 (e) are evolution diagrams of field distributions released along a given direction for stored signal light according to an embodiment of the present invention.
Fig. 5(a) -5 (b) are time domain evolution diagrams of the optical energy of the pulse signal light capture region and the output power of the photonic crystal waveguide in the signal light storage and release processes according to the embodiment of the invention.
The reference numbers illustrate: 1-wavelength tunable pulsed laser; 2-a power tunable pulsed laser; 3-a variable optical attenuator; 4-a fiber optic coupler; 5-a polarization controller; 6-a first lensed fiber; 7-a second lensed fiber; 8-a first optical switch; 9-a second optical switch; 10-a first microlens; 11-a second microlens; 12-photonic crystal waveguide structures; 13-a spectrum analyzer; 14-photonic crystal waveguides; 15-a first index of refraction dynamic modulation region; 16-a second dynamic refractive index modulation region; 17-pulsed signal light trapping region.
Detailed Description
In order to make the technical solutions better understood by those skilled in the art, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It is to be understood that the embodiments described are only a few embodiments of the present application and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
Reference in the specification to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the specification. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present application, "plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.
As shown in fig. 1, the photonic crystal dynamic microcavity-based optical storage device of this embodiment includes a wavelength tunable Pulse laser (Pulse LD)1, a power tunable Pulse laser (Pump LD)2, a Variable Optical Attenuator (VOA)3, an optical Fiber Coupler (FC)4, a polarization controller 5, a first lens fiber 6, a second lens fiber 7, a first optical switch 8, a second optical switch 9, a first microlens 10, a second microlens 11, and a photonic crystal waveguide structure 12.
Further, the photonic crystal waveguide structure 12 includes a photonic crystal waveguide 14 formed by removing 1 entire row of air holes along the x direction from the center of the photonic crystal, and a first refractive index dynamic modulation region 15, a second refractive index dynamic modulation region 16, and a pulse signal light trapping region 17 defined on the photonic crystal waveguide 14; the first refractive index dynamic modulation region, the second refractive index dynamic modulation region and the pulse signal light capture region form a photonic crystal dynamic microcavity.
A signal emitted by the wavelength tunable pulse laser 1 passes through the variable optical attenuator 3, the polarization controller 5 and the first lens optical fiber 6 and then is incident into the photonic crystal waveguide and enters a pulse signal light capturing area; the signal sent by the power-adjustable pulse laser 2 is divided into two paths of light after passing through the optical fiber coupler 4, one path of light is pumped to the first dynamic refractive index modulation region on the photonic crystal waveguide after passing through the first optical switch 8 and the first micro lens 10, and the other path of light is pumped to the second dynamic refractive index modulation region on the photonic crystal waveguide after passing through the second optical switch and the second micro lens in sequence.
Furthermore, the working wavelength of the wavelength tunable pulse laser 1 is continuously tunable from 1500nm to 1700nm, the tuning precision is 1MHz, the pulse width is 10ps, and the repetition frequency is 350 MHz.
Further, the center wavelength of the power tunable pulse laser 2 is λ ═ (415 ± 2) nm, the pulse width is 1.5ps, and the repetition frequency is 75 MHz.
As shown in fig. 2, the photonic crystal waveguide structure 12 of the present embodiment is formed by 88 × 19 circular air holes in a silicon material flat plate to form a triangular lattice, and arranged along the xy plane. The diameter d of the air hole is 0.524a, wherein a 420nm is the lattice constant of the photonic crystal. The refractive index of the silicon slab is 3.4 and the thickness (perpendicular to the xy-plane) h is 0.5 a. The photonic crystal waveguide structure 12 is composed of a photonic crystal waveguide 14, a first refractive index dynamic modulation region 15 and a second refractive index dynamic modulation region 16, and a pulse signal light trapping region 17. The photonic crystal waveguide 14 is formed by removing 1 entire row of air holes in the center of the photonic crystal in the x-direction.
Further, the first dynamic refractive index modulation region 15 and the second dynamic refractive index modulation region 16 are rectangular regions, each having a length and a width of 6a and 4a, respectively, and a center distance of 14 a; the pulse signal light trapping region 17 is located between the first refractive index dynamic modulation region 15 and the second refractive index dynamic modulation region 16. The first refractive index dynamic modulation region 15, the second refractive index dynamic modulation region 16 and the pulse signal light capture region 17 form a photonic crystal dynamic microcavity.
Another embodiment of the present application provides an optical storage method based on a photonic crystal dynamic microcavity, including the following steps:
s1, setting a pair of pulse signal light capturing regions 17 in advance on the photonic crystal waveguide 14; a first refractive index dynamic modulation region 15 and a second refractive index dynamic modulation region 16 are provided at both ends of the region; the center distance of the first refractive index dynamic modulation region 15 and the second refractive index dynamic modulation region 16 was set to 14a so that the resonance wavelength of the photonic crystal dynamic microcavity formed when the refractive index was dynamically modulated was 1670 nm.
S2, turning on the wavelength tunable pulse laser 1, adjusting its center wavelength to 1670nm, adjusting the variable optical attenuator 3 to adjust its power to 1 mw, and using the polarization controller 5 to make the electric field polarization of the wavelength tunable pulse laser 1 along the direction parallel to the xy plane (i.e. transverse electric wave, TE polarization). As shown in fig. 1, a signal light emitted from the wavelength tunable pulse laser 1 is focused by the first lens fiber 6 and then enters the photonic crystal waveguide 14 along a two-dimensional photonic crystal plane (i.e., xy plane), and timing is started. Since the power tunable pulse laser is not turned on temporarily and the optical barrier is not formed yet, the incident pulse signal light is transmitted freely along the photonic crystal waveguide 14, as shown in fig. 3(a) -3 (d); in this embodiment, a 415nm pulse laser is preferable.
S3, when the pulse signal light passes through the predetermined capturing region 17, the 415nm pulse laser is instantaneously turned on. A laser beam emitted by the 415nm pulse laser is divided into two paths of light by a 50:50 optical fiber beam splitting coupler (FC), wherein one path of light sequentially passes through a first optical switch 8 and a first microlens 10, and the other path of light sequentially passes through a second optical switch 9 and a second microlens 11, and then the first refractive index dynamic modulation region 15 and the second refractive index dynamic modulation region 16 at two ends of the pulse signal light capturing region 17 are simultaneously optically pumped, as shown in fig. 3(e), wherein regions indicated by two arrows in fig. 3(e) are the first refractive index dynamic modulation region 15 and the second refractive index dynamic modulation region 16. The free carrier absorption effect generated by the optical pumping instantaneously reduces the refractive indexes of the first refractive index dynamic modulation region 15 and the second refractive index dynamic modulation region 16 at the two ends of the pulse signal light trapping region 17 to form two light barriers, and traps the pulse signal light between the two light barriers to realize high-efficiency light storage, as shown in fig. 3(f) -3 (h).
S4, when the pulse signal light needs to be released at a certain time after being stored for a certain time, stopping optical pumping for any one of the first refractive index dynamic modulation region 15 and the second refractive index dynamic modulation region 16 at both ends of the pulse signal light trapping region 17, so that the optical barrier at the position disappears and a release channel is formed, thereby rapidly releasing the stored pulse signal light from the channel.
Further, in this embodiment, when t is 60ps, the second optical switch 9 is momentarily turned off, and the optical pumping is stopped for the second refractive index dynamic modulation region 16, so that the optical barrier at that position disappears, and the pulse signal light is released in the right direction along the photonic crystal waveguide 14, as shown in fig. 4(a) -4 (e).
Further, the released pulse signal light is received by the spectrum analyzer 13 after passing through the second lens fiber 7. In the optical storage and release process of this embodiment, the time domain evolution diagrams of the optical energy of the pulse signal optical capture region and the output optical power of the photonic crystal waveguide are shown in fig. 5(a) -5 (b), respectively.
The above embodiments are only used to illustrate the technical solutions of the present application, and not to limit the same; although the present application has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not necessarily depart from the spirit and scope of the corresponding technical solutions in the embodiments of the present application.
Claims (10)
1. The controllable optical storage device based on the photonic crystal dynamic microcavity is characterized by comprising a wavelength tunable pulse laser, a power tunable pulse laser, a variable optical attenuator, an optical fiber coupler, a polarization controller, a first lens optical fiber, a second lens optical fiber, a first optical switch, a second optical switch, a first micro lens, a second micro lens and a photonic crystal waveguide structure; the photonic crystal waveguide structure comprises a photonic crystal waveguide, a first refractive index dynamic modulation area, a second refractive index dynamic modulation area and a pulse signal light capture area, wherein the first refractive index dynamic modulation area, the second refractive index dynamic modulation area and the pulse signal light capture area are defined on the photonic crystal waveguide, and the photonic crystal waveguide is formed by removing 1 whole line of air holes from the center of a photonic crystal along the x direction; the first refractive index dynamic modulation region, the second refractive index dynamic modulation region and the pulse signal light capture region form a photonic crystal dynamic microcavity;
the signal light emitted by the wavelength tunable pulse laser passes through the variable optical attenuator, the polarization controller and the first lens fiber and then is emitted into the photonic crystal waveguide and enters the pulse signal light capturing area; a signal emitted by the power-adjustable pulse laser is divided into two paths of light after passing through the optical fiber coupler, one path of light pumps a first dynamic refractive index modulation region on the photonic crystal waveguide after passing through the first optical switch and the first micro lens, and the other path of light pumps a second dynamic refractive index modulation region on the photonic crystal waveguide after passing through the second optical switch and the second micro lens in sequence;
the wavelength tunable pulse laser is used for providing incident signal light; the power-adjustable pulse laser is used for optically pumping the dynamic modulation region of the refractive index of the photonic crystal waveguide; the optical switch is used for switching on or off the optical pump for the refractive index dynamic modulation region of the photonic crystal waveguide.
2. The controllable optical storage device based on photonic crystal dynamic microcavity of claim 1, wherein the photonic crystal waveguide structure is formed by circular air holes in a slab of silicon material to form a triangular lattice; the diameter of the air hole is 0.524a, wherein a is the lattice constant of the photonic crystal; the thickness of the silicon material flat plate is 0.5 a; the first refractive index dynamic modulation region and the second refractive index dynamic modulation region are formed by two identical rectangular regions on the photonic crystal waveguide, the length and the width of each rectangular region are 6a and 4a respectively, and the center distance of the two rectangular regions is 10a to 20 a; the pulse signal light capture region is located between the first refractive index dynamic modulation region and the second refractive index dynamic modulation region.
3. A controllable optical storage device based on a photonic crystal dynamic microcavity as claimed in claim 1 or 2, wherein the resonant frequency of the photonic crystal dynamic microcavity is controlled by adjusting the center distance of the first and second refractive index modulation regions; the center frequency of incident pulse signal light generated by the wavelength tunable pulse laser is the same as the resonance frequency of the photonic crystal dynamic microcavity.
4. The controllable optical storage device based on the photonic crystal dynamic microcavity as claimed in claim 1, wherein the wavelength tunable pulse laser has a working wavelength that is continuously tunable from 1500nm to 1700nm, a tuning precision of 1MHz, a pulse width of 10ps, and a repetition frequency of 350 MHz.
5. A controllable optical storage device based on photonic crystal dynamic microcavities as claimed in claim 1 wherein said power tunable pulsed laser has a center wavelength λ ═ (415 ± 2) nm, a pulse width of 1.5ps, and a repetition rate of 75 MHz.
6. A controllable optical storage device according to claim 1, wherein said fiber coupler is a 50:50 fiber coupler.
7. The method of any of claims 1-6, comprising the steps of:
s1, presetting a pulse signal light capturing area on the photonic crystal waveguide, wherein a first refractive index dynamic modulation area and a second refractive index dynamic modulation area are arranged at two ends of the area; adjusting the center distance between the first refractive index dynamic modulation region and the second refractive index dynamic modulation region, so that the resonance wavelength of the photonic crystal dynamic microcavity formed when the refractive indexes are dynamically modulated is the center wavelength of the pulse signal light;
s2, starting a wavelength tunable pulse laser, and tuning the central wavelength of the pulse laser to the resonance wavelength of the photonic crystal dynamic microcavity; pulse signal light emitted by the tunable pulse laser is incident from the left end of the photonic crystal waveguide and is transmitted along the photonic crystal waveguide;
s3, when the pulse signal light passes through a preset capture area, instantly starting the power-adjustable pulse laser, and simultaneously optically pumping a first refractive index dynamic modulation area and a second refractive index dynamic modulation area at two ends of the capture area, so that the refractive indexes of the first refractive index dynamic modulation area and the second refractive index dynamic modulation area are instantly reduced to form two optical barriers, and capturing the pulse signal light between the two optical barriers to realize optical storage;
and S4, when the pulse signal light needs to be released at a certain moment in storage for a certain time, stopping optical pumping for any one of the dynamic refractive index modulation regions at two ends of the capture region by closing the optical switch, so that the optical barrier at the position disappears and a release channel is formed, and the stored pulse signal light is rapidly released from the channel along a given direction.
8. The optical storage method according to claim 7, wherein in step S1, the center distance between the first refractive index dynamic modulation region and the second refractive index dynamic modulation region is set to 10a to 20a, so that the resonant wavelength of the photonic crystal dynamic microcavity formed when the refractive index is dynamically modulated is in the range of 1660-.
9. The optical storage method according to claim 7, wherein in step S2, the signal light emitted by the wavelength tunable pulse laser is focused by the first lens fiber and then emitted into the photonic crystal waveguide along the two-dimensional photonic crystal plane, and timing is started; because the power adjustable pulse laser is not started temporarily and the light barrier is not formed yet, the incident pulse signal light is transmitted freely along the photonic crystal waveguide.
10. The optical storage method of claim 7, wherein in step S3, the laser beam emitted by the wavelength tunable pulse laser is split into two paths of light by the fiber beam splitter coupler, wherein one path of light sequentially passes through the first optical switch and the first microlens, and the other path of light sequentially passes through the second optical switch and the second microlens, and then the first dynamic refractive index modulation region and the second dynamic refractive index modulation region at both ends of the pulse signal light capture region are optically pumped simultaneously.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110774015.3A CN113658613B (en) | 2021-07-08 | 2021-07-08 | Controllable optical storage device and method based on photonic crystal dynamic microcavity |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110774015.3A CN113658613B (en) | 2021-07-08 | 2021-07-08 | Controllable optical storage device and method based on photonic crystal dynamic microcavity |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113658613A true CN113658613A (en) | 2021-11-16 |
| CN113658613B CN113658613B (en) | 2022-04-22 |
Family
ID=78477191
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110774015.3A Active CN113658613B (en) | 2021-07-08 | 2021-07-08 | Controllable optical storage device and method based on photonic crystal dynamic microcavity |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113658613B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102722061A (en) * | 2012-06-15 | 2012-10-10 | 华南理工大学 | All-optical multi-wavelength conversing method and device based on photonic crystal |
| CN105720475A (en) * | 2016-03-23 | 2016-06-29 | 华南理工大学 | Unidirectional optical transmitting method and apparatus for photonic crystal based all-optical diode |
| US20180019564A1 (en) * | 2015-02-19 | 2018-01-18 | B.G. Negev Technologies And Applications Ltd., At Ben-Gurion University | Transient bragg gratings in optical waveguides and their applications |
| CN108390249A (en) * | 2018-05-18 | 2018-08-10 | 华南理工大学 | Dynamic Q-modulating device based on photon crystal micro cavity and method |
| CN109683242A (en) * | 2019-02-28 | 2019-04-26 | 华南理工大学 | A kind of controllable uni-directional light flow device and method of all-optical diode |
-
2021
- 2021-07-08 CN CN202110774015.3A patent/CN113658613B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102722061A (en) * | 2012-06-15 | 2012-10-10 | 华南理工大学 | All-optical multi-wavelength conversing method and device based on photonic crystal |
| US20180019564A1 (en) * | 2015-02-19 | 2018-01-18 | B.G. Negev Technologies And Applications Ltd., At Ben-Gurion University | Transient bragg gratings in optical waveguides and their applications |
| CN105720475A (en) * | 2016-03-23 | 2016-06-29 | 华南理工大学 | Unidirectional optical transmitting method and apparatus for photonic crystal based all-optical diode |
| CN108390249A (en) * | 2018-05-18 | 2018-08-10 | 华南理工大学 | Dynamic Q-modulating device based on photon crystal micro cavity and method |
| CN109683242A (en) * | 2019-02-28 | 2019-04-26 | 华南理工大学 | A kind of controllable uni-directional light flow device and method of all-optical diode |
Non-Patent Citations (1)
| Title |
|---|
| 周建伟 等: "《光控液晶光子晶体微腔全光开关》", 《物理学报》 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113658613B (en) | 2022-04-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| WO2006042239A2 (en) | Cascaded cavity silicon raman laser with electrical modulation, switching, and active mode locking capability | |
| CN115268162B (en) | Nonlinear optical device | |
| Santagiustina et al. | Slow light devices and their applications to microwaves and photonics | |
| CN109802290A (en) | Based on ultrashort pulse fiber laser infrared in synchronizing mode-licked | |
| CN105720475B (en) | A kind of all-optical diode uni-directional light flow method and device based on photonic crystal | |
| CN115173215A (en) | High-repetition-frequency broad-spectrum femtosecond pulse generating device based on-chip Kerr optical microcavity | |
| CA2843546A1 (en) | Wave vector matched resonator and bus waveguide system | |
| CN113658613B (en) | Controllable optical storage device and method based on photonic crystal dynamic microcavity | |
| CN108390249B (en) | Dynamic Q-switching device and method based on photonic crystal microcavity | |
| Watts et al. | Maximally confined high-speed second-order silicon microdisk switches | |
| WO2015018048A1 (en) | Reflective thermo-optic variable optical attenuator | |
| CN110676683A (en) | Acousto-optic electromechanical linkage multi-wavelength tunable synchronous light source | |
| JP5164897B2 (en) | Optical filter | |
| CN209514132U (en) | A kind of controllable uni-directional light flow device of all-optical diode | |
| CN113937605A (en) | Multi-parameter tunable femtosecond pulse laser | |
| Nawi et al. | A theoretical model of all-optical switching induced by a soliton pulse in nano-waveguide ring resonator | |
| CN102570275B (en) | Laser capable of tuning wavelengths | |
| CN103956645A (en) | Fast-light-tunable device based on stimulated Brillouin scattering | |
| CN109683242A (en) | A kind of controllable uni-directional light flow device and method of all-optical diode | |
| TWI740621B (en) | Push-pull tunable optical delay line and phase shifter | |
| Tan et al. | Nonlinear optical signal processing in CMOS-compatible ultra-silicon-rich nitride devices | |
| Zhang et al. | All-optical non-volatile tuning of nanobeam resonators using the GST phase-change material | |
| Soares et al. | Tunable third-harmonic generation in silicon oxide wedge microcavities | |
| Tan et al. | Photonic RF and microwave fractional differentiation, integration, and Hilbert transforms with Kerr optical micro-combs | |
| Moss | Photonic microwave and RF programmable true time delays for phased array antennas using a soliton crystal Kerr micro-comb source |
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 |