Method and device for regulating spectral beam splitting of an optical signal

Abstract

The application discloses a kind of light signal spectrum beam splitting's regulation and control method and device, regulation and control method includes: S1, light frequency comb is incident to first electro-optic phase modulator, obtains first optical signal;Light frequency comb frequency interval is same with the frequency of driving electric signal loaded on first electro-optic phase modulator;S2, first optical signal is input into second electro-optic phase modulator, obtains n beam splitting optical signals;Driving electric signal frequency loaded on first electro-optic phase modulator is n times of driving electric signal frequency loaded on second electro-optic phase modulator, and n beam splitting optical signals obtained by second electro-optic phase modulator modulation carry n kinds of total bloch momentum respectively.The device includes mode-locked laser, first electro-optic phase modulator, second electro-optic phase modulator, two electric modulation modules and electric signal output module.The application constructs photonic lattice with different lattice constants, and realizes controllable beam splitting for light signal spectrum, so as to realize frequency division multiplexing.

Description

Technical Field

[0001] This invention relates to the field of optical signal processing technology, and more specifically, to a method and apparatus for controlling optical signal spectrum self-splitting. Background Technology

[0002] Photons, with their superior properties such as ultra-high speed and low loss, have become an important medium for simulating electronic behavior and overcoming the bottlenecks of traditional electronic devices. The introduction of the synthesis dimension provides a new degree of freedom for controlling photonic behavior, making it possible to simulate condensed matter physics phenomena in non-spatial dimensions such as frequency. In practical applications, the control of optical signals is also significant, such as in photonic neural networks and precision optical measurements, opening up new avenues for researching photonic devices.

[0003] In the field of optical signal processing technology, the manipulation of the synthesis dimension is a research hotspot. Invention patent CN 108512604A discloses a method and device for frequency modulation of optical signals. By changing the Bloch phase of the optical frequency comb, the refraction and reflection of the optical signal are controlled, achieving real-time control and continuous adjustment of the frequency conversion efficiency and direction of the optical signal. Existing work still focuses on frequency lattices with a single lattice constant, where wave packets in frequency-domain photonic lattices still propagate in a single propagation mode after refraction. However, with the development of applications in optical communication and integrated circuits, and the deepening research on the construction mechanism and physical effects of heterogeneous lattice systems, the manipulation of lattices with a single lattice constant is insufficient to meet the requirements of parallel and frequency-division multiplexing of optical signals in the frequency dimension. More and more application scenarios are placing new demands on the controllable beam splitting of optical signal spectra.

[0004] Therefore, there is an urgent need for a new mechanism and method for controlling the propagation and evolution of optical signals to achieve self-splitting of the optical signal spectrum and solve the problems of existing discrete photonics systems that control beam evolution, which are limited to the control of a single lattice constant, cannot achieve controllable beam splitting for the optical signal spectrum, and cannot be frequency-division multiplexed. Summary of the Invention

[0005] To address the limitations of existing beam evolution control systems, which are restricted to controlling lattices with single lattice constants and cannot achieve controllable beam splitting or frequency division multiplexing based on the optical signal spectrum, this invention provides a method and apparatus for controlling optical signal spectrum self-splitting. The aim is to construct photonic lattices with different lattice constants to achieve controllable beam splitting based on the optical signal spectrum, thereby realizing frequency division multiplexing.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: According to a first aspect of the present invention, a method for controlling optical signal spectrum self-splitting is provided, comprising: S1, a beam of optical frequency comb is incident on the first electro-optic phase modulator to obtain a first optical signal; the frequency interval of the optical frequency comb is the same as the frequency of the driving electrical signal loaded on the first electro-optic phase modulator. S2, the first optical signal is input into the second electro-optic phase modulator to obtain n split optical signals; the frequency of the driving electrical signal loaded on the first electro-optic phase modulator is n times the frequency of the driving electrical signal loaded on the second electro-optic phase modulator, and the phase of the driving electrical signal loaded on the second electro-optic phase modulator satisfies the following: the n split optical signals obtained by the second electro-optic phase modulator each carry n kinds of total Bloch momentum, and the n kinds of total Bloch momentum are respectively 1= , 2= + (2π / n ), 3= + 2(2π / n ),...、 n = + ( n - 1)(2π / n ); in, Let n be the total Bloch momentum of the first split optical signal; n is a positive integer and greater than 1.

[0007] Preferably, n=2; the phase of the driving electrical signal loaded on the second electro-optic phase modulator also satisfies: =π / 2.

[0008] Preferably, n=3; the phase of the driving electrical signal loaded on the second electro-optic phase modulator also satisfies: =π / 3.

[0009] Preferably, n=6; the phase of the driving electrical signal loaded on the second electro-optic phase modulator also satisfies: = .

[0010] According to a second aspect of the present invention, an optical signal spectrum self-beam splitting device is provided, comprising: a mode-locked laser, a first electro-optic phase modulator, a second electro-optic phase modulator, two electro-modulation modules, and an electrical signal output module, wherein the two electro-modulation modules are the first electro-modulation module and the second electro-modulation module, respectively. The mode-locked laser, the first electro-optic phase modulator, and the second electro-optic phase modulator are arranged sequentially along the optical path; Mode-locked lasers are used to provide optical frequency combs; The first electro-optic phase modulator is used to phase modulate the optical frequency comb so that the optical signal generation mode transitions. The second electro-optic phase modulator is used to modulate the frequency and phase of the optical frequency comb emitted by the first electro-optic phase modulator in order to achieve controllable beam splitting of the optical signal. The electrical signal output module has three output terminals, which are respectively connected to the mode-locked laser, the first electro-optic phase modulator, and the second electro-optic phase modulator. The electrical signal output module is used to provide driving electrical signals to the mode-locked laser, the first electro-optic phase modulator, and the second electro-optic phase modulator, satisfying that the frequency interval of the optical frequency comb provided by the mode-locked laser is the same as the frequency of the driving electrical signal loaded on the first electro-optic phase modulator, and the frequency of the driving electrical signal loaded on the first electro-optic phase modulator is n times the frequency of the driving electrical signal loaded on the second electro-optic phase modulator. The first electrical modulation module is located between the electrical signal output module and the first electro-optic phase modulator, and is used to adjust the amplitude and phase of the driving electrical signal entering the first electro-optic phase modulator; The second electro-modulation module is located between the electrical signal output module and the second electro-optic phase modulator. It is used to adjust the amplitude and phase of the driving electrical signal entering the second electro-optic phase modulator, ensuring that the phase of the driving electrical signal loaded on the second electro-optic phase modulator satisfies the following condition: the n beam-splitting optical signals modulated by the second electro-optic phase modulator each carry n types of total Bloch momentum, and the n types of total Bloch momentum are respectively... 1= , 2= + (2π / n ), 3= + 2(2π / n ),...、 n = + ( n - 1)(2π / n ).

[0011] Preferably, the electro-modulation module includes a radio frequency amplifier, an adjustable attenuator, and a radio frequency phase shifter connected in sequence. The radio frequency amplifier and the adjustable attenuator are used to adjust the amplitude of the driving electrical signal entering the electro-optic phase modulator, and the radio frequency phase shifter is used to adjust the phase of the driving electrical signal entering the electro-optic phase modulator. The RF amplifier is connected to the electrical signal output module, and the RF phase shifter is connected to the corresponding electro-optic phase modulator.

[0012] Preferably, the electrical signal output module includes a first power divider, a frequency multiplier, a second power divider, and a radio frequency signal source; Radio frequency (RF) signal sources are used to generate sinusoidal RF signals as driving electrical signals. The second power divider is connected to the radio frequency signal source and is used to divide the power of the driving electrical signal output by the radio frequency signal source to obtain the original frequency driving electrical signal and the second driving electrical signal; the second driving electrical signal is connected to the second electro-optic phase modulator from the second output terminal. The frequency multiplier is set at the first output terminal of the second power divider to increase the frequency of the original frequency driving signal by a factor of n to obtain the frequency multiplier driving signal. The input of the first power divider is connected to the output of the frequency multiplier, and is used to divide the power of the frequency multiplication drive signal to obtain the initial drive signal and the first drive signal; the initial drive signal is directed to the mode-locked laser, and the first drive signal is directed to the first electro-optic phase modulator.

[0013] Preferably, it further includes an optical frequency comb modulation module disposed between the mode-locked laser and the first electro-optic phase modulator; The optical frequency comb modulation module includes a programmable optical filter and a polarization controller arranged sequentially along the optical path. The programmable optical filter is used to perform Gaussian filtering on the optical frequency comb generated by the mode-locked laser, and the polarization controller is used to adjust the polarization of the filtered optical frequency comb.

[0014] Preferably, it further includes an initial adjustable attenuator disposed between the first power divider and the mode-locked laser, for adjusting the initial drive electrical signal strength applied to the mode-locked laser.

[0015] Preferably, it also includes a spectrometer located along the optical path on the output side of the second electro-optic phase modulator for detecting and recording the emitted spectrum.

[0016] In summary, compared with the prior art, the technical solutions conceived in this invention have the following technical effects: 1. This invention provides a method for controlling the self-splitting of optical signal spectrum. By loading a driving electrical signal with the same frequency interval as the optical frequency comb onto a first electro-optic phase modulator and a driving electrical signal with a frequency interval of 1 / n onto a second electro-optic phase modulator, photonic lattices are synthesized and manipulated in the frequency dimension to construct equivalent frequency heterogeneous interfaces with different lattice constants. This causes degeneracy splitting when the optical frequency comb is incident, inducing self-splitting of the optical signal. This solves the problem that existing systems are limited to the control of lattices with a single lattice constant, and provides a new method for controllable beam splitting and frequency division multiplexing of optical signal spectrum. 2. This invention provides preferred schemes for optical signal spectrum self-splitting in three cases, namely: when n=2, =π / 2; when n=3 =π / 3; when n=6 = These three preferred schemes can achieve the maximum separation angle and the highest energy utilization efficiency for the corresponding number of beam splitting optical signals. 3. This invention provides an optical signal spectrum self-beam splitter, which changes the driving electrical signal parameters by combining electrical signal modulation devices, thereby realizing flexible control of optical signal beam splitting, frequency, phase and power. The entire modulation process does not require changing the optical devices themselves or introducing complex nonlinear optical pumps. The structure is simple and the modulation method is convenient. Attached Figure Description

[0017] Figure 1 This is a flowchart of the optical signal spectrum self-splitting modulation method provided by the present invention.

[0018] Figure 2 This is a schematic diagram of the optical signal spectrum self-splitting control device provided by the present invention.

[0019] Figure 3 The diagram shows the discrete frequency lattice and lattice band structure of the optical frequency comb provided by the present invention; wherein, (a) is a lattice diagram showing near-neighbor coupling when the lattice constant is a and long-range coupling when the lattice constant is 2a; (b) is a lattice band structure showing near-neighbor coupling when the lattice constant is a and long-range coupling when the lattice constant is 2a; (c) is a lattice diagram showing near-neighbor coupling when the lattice constant is a and long-range coupling when the lattice constant is 3a; and (d) is a lattice band structure showing near-neighbor coupling when the lattice constant is a and long-range coupling when the lattice constant is 3a.

[0020] Figure 4 This is a schematic diagram of the band structure and evolution of a light signal spectrum with n=2 provided in Embodiment 1 of the present invention.

[0021] Figure 5 This is a schematic diagram of the band structure and evolution of the optical signal spectrum self-splitting with n=3 provided in Embodiment 2 of the present invention.

[0022] Figure 6 This is a schematic diagram of the band structure and evolution of the optical signal spectrum self-splitting with n=6 provided in Embodiment 3 of the present invention.

[0023] In all the accompanying drawings, the same reference numerals are used to denote the same elements or structures. Wherein: 1-Mode-locked laser, 2-Optical frequency comb modulation module, 3-First electro-optic phase modulator, 4-Second electro-optic phase modulator, 5-Spectrometer, 6-Initial adjustable attenuator, 7-First electrical modulation module, 8-Second electrical modulation module, 9-Electrical signal output module, 21-Programmable optical filter, 22-Polarization controller, 71-First radio frequency phase shifter, 72-First adjustable attenuator, 73-First radio frequency amplifier, 81-Second radio frequency phase shifter, 82-Second adjustable attenuator, 83-Second radio frequency amplifier, 91-First power divider, 92-Frequency multiplier, 93-Second power divider, 94-Radio frequency signal source. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0025] In this invention, the terms "first," "second," etc., used in the invention and accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0026] Firstly, see [the following] Figure 1 This invention provides a method for controlling the self-splitting of optical signal spectrum, comprising: S1, a beam of optical frequency comb is incident on the first electro-optic phase modulator to obtain a first optical signal; the frequency interval of the optical frequency comb is the same as the frequency of the driving electrical signal loaded on the first electro-optic phase modulator.

[0027] S2, the first optical signal is input into the second electro-optic phase modulator to obtain n split optical signals; the frequency of the driving electrical signal loaded on the first electro-optic phase modulator is n times the frequency of the driving electrical signal loaded on the second electro-optic phase modulator, and the phase of the driving electrical signal loaded on the second electro-optic phase modulator satisfies the following: the n split optical signals obtained by the second electro-optic phase modulator each carry n kinds of total Bloch momentum, and the n kinds of total Bloch momentum are respectively 1= , 2= + (2π / n ), 3= + 2(2π / n ),...、 n = + ( n - 1)(2π / n );in, Let n be the total Bloch momentum of the first split optical signal; n is a positive integer and greater than 1.

[0028] First, the principle behind the above-mentioned control methods will be explained: An optical frequency comb consists of a series of discrete coherent optical frequency components spaced uniformly in the frequency domain. Its spectral shape resembles a comb, with each tooth considered as an artificial lattice point. The radio frequency signal loaded onto the electro-optic phase modulator periodically modulates the refractive index of the waveguide through the electro-optic effect. Under the influence of refractive index modulation, mode transitions occur in the photonic baseband. During the frequency transition, a phase is acquired when transitioning from the nth mode to the (n+1)th mode. + A reverse transition will obtain a phase. This geometric phase corresponds to the equivalent photonic gauge potential in the frequency dimension. The effect of the gauge potential is to cause a shift in the band structure. Therefore, when the frequency interval of the optical frequency comb changes, the lattice band structure changes.

[0029] When driving electrical signals of different frequencies are applied to a mode-locked laser and multiple electro-optic phase modulators, the mode-locked laser generates optical frequency combs with corresponding frequency intervals, and the electro-optic phase modulators construct photonic lattices with different lattice constants. If the frequency of the driving electrical signal applied to the second electro-optic phase modulator is denoted as 'a', then the initial frequency interval of the optical frequency comb is 'na', and the frequency of the driving electrical signal applied to the first electro-optic phase modulator is also 'na'.

[0030] When the optical frequency comb enters the first electro-optic phase modulator, photons transition at frequency intervals of na. Therefore, the frequency interval of the first optical signal remains unchanged, and the first optical signal obtained after passing through the first electro-optic phase modulator has a single total Bloch momentum.

[0031] The total Bloch momentum of the first optical signal na = 0na - na Equivalent lattice band structure of Bloch mode optical frequency comb ω na ( k ) = 2 C cos( 0na - na ), Where C is the coupling strength; k is the Bloch wave vector. k [- π / na , π / na ]; 0na Let be the initial Bloch momentum of the first optical signal. 0na =Ω k， Ω is the frequency of the driving electrical signal, where Ω = na , a is the frequency of the driving electrical signal applied to the second electro-optic phase modulator; na For modulation phase; When the optical frequency comb enters the second electro-optic phase modulator, its degenerate state is split on the output side, inducing self-splitting behavior of the wave packet. The total Bloch momentum of the controllable beam splitting... a = 0a - a The equivalent lattice band structure of a beam-splitting Bloch mode optical frequency comb ω a ( k ) = 2 C cos( 0a - a ), Where C is the coupling strength; k is the Bloch wave vector. k ∈[-π / a , π / a ]; 0a Let be the initial Bloch momentum of the split beam signal. 0a =Ω k， Ω is the frequency of the driving electrical signal, where Ω = a ; a is the frequency of the driving electrical signal applied to the second electro-optic phase modulator; a For modulation phase; It can be seen that the equivalent lattice band period of the split optical signal is n times that of the first optical signal. When the optical frequency comb enters the second electro-optic phase modulator and undergoes a frequency transition, its total Bloch momentum undergoes an equivalent mapping on the new band. Therefore, the n split optical signals carry n different types of total Bloch momentum, respectively. 1= , 2= +(2π / n ), 3= + 2(2π / n ),...、 n = + (n - 1)(2π / n ).

[0032] Because the propagation of light signals generates transverse group velocity v g Horizontal offset of the center Δ ω And diffraction broadening, in which: Lateral group velocity v g = -2ΩCsin( ) , characterizing the energy and information transmission rate of a wave packet perpendicular to its main propagation direction; Center Lateral Offset Δω=-m Ωsin( ) It characterizes the overall positional offset of the wave packet in the lateral direction, reflecting the degree of deviation of its energy center relative to the reference axis; The absolute value of diffraction broadening is positively correlated with the broadening factor. D=2CΩ 2 cos( ) Diffraction broadening characterizes the degree of diffusion of the transverse dimension of a wave packet as the distance increases due to the diffraction effect during propagation. The smaller the diffraction broadening, the more concentrated the energy distribution. In the above formula, Ω represents the total Bloch momentum of the optical signal; Ω is the frequency of the driving electrical signal. m =2CL,m Where C is the phase modulation depth, C is the coupling strength, and L is the length of the electro-optic phase modulator.

[0033] Therefore, the n beams of light carrying n different total Bloch momentum evolve in n different ways.

[0034] Simultaneously, by adjusting the phase of the driving electrical signal applied to the electro-optic phase modulator, the total Bloch momentum of the optical signal can be continuously adjusted, thus enabling the transverse group velocity to be... v g Horizontal offset of center Δ ω The diffraction broadening changes accordingly; by adjusting the intensity of the driving electrical signal applied to the electro-optic phase modulator, the coupling strength C can be changed, thereby altering the phase modulation depth and realizing the transverse group velocity of the optical signal. v g and center lateral offset Δ ω Continuously adjustable.

[0035] Secondly, see Figure 2 The present invention provides an optical signal spectrum self-splitting device, comprising: a mode-locked laser 1, a first electro-optic phase modulator 3, a second electro-optic phase modulator 4, two electro-modulation modules and an electrical signal output module 9, wherein the two electro-modulation modules are a first electro-modulation module 7 and a second electro-modulation module 8.

[0036] The mode-locked laser 1, the first electro-optic phase modulator 3, and the second electro-optic phase modulator 4 are arranged sequentially along the optical path.

[0037] Mode-locked laser 1 is used to provide an optical frequency comb.

[0038] The first electro-optic phase modulator 3 is used to modulate the phase of the laser in the optical frequency comb so that the photon generation mode transitions and the optical signal evolves.

[0039] The second electro-optic phase modulator 4 is used to modulate the frequency and phase of the laser emitted from the optical frequency comb of the first electro-optic phase modulator 3, so as to achieve controllable beam splitting of the optical signal.

[0040] The electrical signal output module 9 has three output terminals, which are respectively connected to the mode-locked laser 1, the first electro-optic phase modulator 3, and the second electro-optic phase modulator 4. The electrical signal output module 9 is used to provide driving electrical signals to the mode-locked laser 1, the first electro-optic phase modulator 3, and the second electro-optic phase modulator 4, such that the frequency interval of the optical frequency comb provided by the mode-locked laser 1 is the same as the frequency of the driving electrical signal loaded on the first electro-optic phase modulator, and the frequency of the driving electrical signal loaded on the first electro-optic phase modulator 3 is n times the frequency of the driving electrical signal loaded on the second electro-optic phase modulator 4.

[0041] The first electrical modulation module 7 is located between the electrical signal output module 9 and the first electro-optic phase modulator 3, and is used to adjust the amplitude and phase of the driving electrical signal entering the first electro-optic phase modulator 3. The second electrical modulation module 8 is located between the electrical signal output module 9 and the second electro-optic phase modulator 4. It is used to adjust the amplitude and phase of the driving electrical signal entering the second electro-optic phase modulator 4, ensuring that the phase of the driving electrical signal loaded on the second electro-optic phase modulator 4 satisfies the following: the n beam-splitting optical signals modulated by the second electro-optic phase modulator 4 each carry n types of total Bloch momentum, and the n types of total Bloch momentum are respectively... 1= , 2= + (2π / n ), 3= + 2(2π / n ),...、 n = + (n - 1)(2π / n ).

[0042] Specifically, the electro-modulation module includes a radio frequency (RF) amplifier, an adjustable attenuator, and an RF phase shifter connected in sequence. The RF amplifier and adjustable attenuator are used to adjust the amplitude of the driving electrical signal entering the electro-optic phase modulator, thereby changing the evolution depth of the optical signal in the electro-optic phase modulator. The RF phase shifter is used to adjust the phase of the driving electrical signal entering the electro-optic phase modulator. The RF amplifier is connected to the electrical signal output module 9, and the RF phase shifter is connected to the corresponding electro-optic phase modulator.

[0043] That is, Figure 2 As shown, the first electrical modulation module 7 sequentially includes a first radio frequency amplifier 73, a first adjustable attenuator 72, and a first radio frequency phase shifter 71. The first radio frequency amplifier 73 is connected to the electrical signal output module 9, and the first radio frequency phase shifter 71 is connected to the first electro-optic phase modulator 3. The second electrical modulation module 7 sequentially includes a second radio frequency amplifier 83, a second adjustable attenuator 82, and a second radio frequency phase shifter 81. The second radio frequency amplifier 83 is connected to the electrical signal output module 9, and the second radio frequency phase shifter 81 is connected to the second electro-optic phase modulator 4.

[0044] Specifically, the electrical signal output module 9 includes a first power divider 91, a frequency multiplier 92, a second power divider 93, and a radio frequency signal source 94.

[0045] The radio frequency signal source 94 is used to generate a sinusoidal radio frequency signal as a driving electrical signal.

[0046] The second power divider 93 is connected to the radio frequency signal source 94 and is used to divide the power of the driving electrical signal output by the radio frequency signal source 94 to obtain the original frequency driving electrical signal and the second driving electrical signal; the second driving electrical signal is connected to the second electro-optic phase modulator 4 from the second output terminal.

[0047] The frequency multiplier 92 is located at the first output terminal of the second power divider 93 and is used to increase the frequency of the original frequency driving electrical signal by a factor of n to obtain a frequency-doubled driving electrical signal. Therefore, the selection of the frequency multiplier determines the number of propagation modes of the optical signal after passing through the second electro-optic phase modulator 4. When a frequency multiplier 92 with a frequency multiplication factor of n is selected, the optical signal has n propagation modes after passing through the second electro-optic phase modulator 4.

[0048] The input terminal of the first power divider 91 is connected to the output terminal of the frequency multiplier 92, and is used to divide the power of the frequency multiplication drive electrical signal to obtain the initial drive electrical signal and the first drive electrical signal; the initial drive electrical signal is directed to the mode-locked laser 1, and the first drive electrical signal is directed to the first electro-optic phase modulator 3.

[0049] Preferably, it also includes an optical frequency comb modulation module 2 disposed between the mode-locked laser 1 and the first electro-optic phase modulator 3.

[0050] The optical frequency comb modulation module 2 includes a programmable optical filter 21 and a polarization controller 22 arranged sequentially along the optical path. The programmable optical filter 21 is used to perform Gaussian filtering on the optical frequency comb generated by the mode-locked laser 1, making the wave packets more concentrated, which is beneficial for subsequent observation; the polarization controller 22 is used to adjust the polarization of the filtered optical frequency comb.

[0051] Optionally, it also includes an initial adjustable attenuator 6 disposed between the first power divider 91 and the mode-locked laser 1, for adjusting the intensity of the initial driving electrical signal loaded on the mode-locked laser 1, thereby adjusting the intensity of the optical frequency comb signal.

[0052] In some embodiments, a spectrometer 5 is also included, located along the optical path at the output side of the second electro-optic phase modulator 4, for detecting and recording the emitted spectrum. All evolution processes of the optical signal, including spectral shift, broadening, and beam splitting, can be directly observed by the spectrometer. The results are intuitive and facilitate experimental verification and analysis of theoretical models, providing an effective experimental platform for the study of synthetic dimensional photonics and non-reciprocal photonic devices.

[0053] To further illustrate the optical signal spectrum self-splitting control method and apparatus provided by the present invention, which realizes controllable n-splitting of optical signals in the frequency dimension, the following detailed description is provided in conjunction with three preferred embodiments: Example 1: A method for controlling the self-beam splitting of an optical signal spectrum, comprising: S1. Select frequency multiplier 92 with n=2, refer to... Figure 2 Install control devices.

[0054] S2. Set the output frequency of the radio frequency signal source 94 to a, and adjust the initial adjustable attenuator 6 so that the initial drive electrical signal is at the normal operating power of the mode-locked laser 1 when it enters the mode-locked laser 1.

[0055] S3. Start the mode-locked laser 1, spectrometer 5, and radio frequency signal source 94. At this time, the radio frequency signal source 94 outputs a sinusoidal radio frequency signal with frequency 'a' as the driving signal. This signal is distributed by the second power divider 93 to obtain the original frequency driving signal and the second driving signal. The original frequency driving signal is output from the first output terminal to the frequency multiplier 92, and the second driving signal is output from the second output terminal to the second electro-optic phase modulator 4. After passing through the n=2 frequency multiplier, the original frequency driving signal generates a frequency-doubled driving signal with a frequency of 2a, making the frequency of the driving signal loaded on the mode-locked laser 1 and the first electro-optic phase modulator 3 twice the frequency of the second driving signal. A photonic lattice with lattice constants of 2a and 'a' is constructed in the frequency dimension, causing the optical frequency comb incident on the second electro-optic phase modulator 4 to change from long-range coupling to near-neighbor coupling. Its discrete frequency lattice and lattice energy band are as follows: Figure 3 (a) Figure 3 As shown in (b).

[0056] S4. Keep the first RF amplifier 73 and the second RF amplifier 83 in the off state, adjust the mode-locked laser 1 to the mode-locked state, adjust the programmable optical filter 21 and the polarization controller 22, the optical frequency comb passes through the programmable optical filter 21 to form a Gaussian-shaped optical frequency comb wave packet, and then passes through the polarization controller 22 to form polarized light.

[0057] S5. Set the total Bloch momentum of the optical frequency comb passing through the first electro-optic phase modulator 3 to be... na =π / 2: Turn on the first RF amplifier 73, adjust the attenuation of the first adjustable attenuator 72 to the minimum, and adjust the first RF phase shifter 71 to shift the output optical frequency comb to the left to the maximum. At this time, the center lateral shift reaches the maximum and the diffraction broadening is the minimum, so that the energy dissipation of the optical frequency comb is minimized in the stage before entering the second electro-optic phase modulator 4.

[0058] S6. Turn on the second RF amplifier 83, adjust the second attenuator 82, and adjust the second RF phase shifter 81 so that the phase of the driving electrical signal loaded on the second electro-optic phase modulator 4 satisfies the desired phase. =π / 2, the total Bloch momentum of the two split optical signals are Φ1=π / 2 and Φ2=3π / 2 respectively, and the energy bands of the optical frequency comb before and after passing through the second electro-optic phase modulator 4 are as follows: Figure 4 As shown in (a), the transverse group velocities of the two obtained beam split signals are respectively v g1 = -2aC、v g2 = 2aC The separation angle between the two split optical signals reaches its maximum.

[0059] S7. The attenuation magnitude of the second adjustable attenuator 82 is increased sequentially, so that the intensity of the electrical signal loaded on the second electro-optic phase modulator 4 gradually decreases, thereby gradually reducing the modulation depth to the point of being off; the attenuation magnitude of the first adjustable attenuator 72 is increased sequentially, so that the intensity of the driving electrical signal loaded on the first electro-optic phase modulator 3 gradually decreases, thereby gradually reducing the modulation depth.

[0060] S8. Record the optical frequency comb spectrum images at different modulation depths during process S7 using a spectrometer. The results are as follows: Figure 4 As shown in (d).

[0061] S9. Adjust the second radio frequency phase shifter 81 so that the total Bloch momentum of the two split optical signals are Φ1=π / 4 and Φ2=5π / 4 respectively. The energy bands of the optical frequency comb before and after passing through the second electro-optic phase modulator 4 are as follows: Figure 4 As shown in (b), the transverse group velocities of the two split-beam optical signals are respectively v g1 =- aC、v g2 = aC The separation angle between the two split light signals decreases; repeating process S7, the optical frequency comb spectrum images at different modulation depths are recorded using a spectrometer, and the results are as follows. Figure 4 As shown in (e).

[0062] S10. Adjust the second radio frequency phase shifter 81 so that the total Bloch momentum of the two split optical signals is Φ1=0 and Φ2=π respectively. The energy bands of the optical frequency comb before and after passing through the second electro-optic phase modulator 4 are as follows: Figure 4 As shown in (c), the transverse group velocities of the two split-beam optical signals are obtained. v g1 =v g2 =0 The two split optical signals propagate in the same direction and do not separate; repeat process S7, and record the optical frequency comb spectrum images at different modulation depths using a spectrometer. The results are as follows: Figure 4 As shown in (f).

[0063] Example 2: A method for controlling the self-splitting of optical signal spectrum. This embodiment is similar to Embodiment 1 above, except that a frequency multiplier 92 with n=3 is selected. In this embodiment, the frequency of the driving electrical signal loaded on the mode-locked laser 1 and the first electro-optic phase modulator 3 is three times the frequency of the second driving electrical signal. At this time, a photonic lattice with lattice constants of 3a and a is constructed in the frequency dimension, so that when the optical frequency comb is incident on the second electro-optic phase modulator 4, it changes from long-range coupling to near-neighbor coupling. Its discrete frequency lattice and lattice energy band are as follows. Figure 3 (c) Figure 3 As shown in (d).

[0064] The first evolution method: By adjusting the second radio frequency phase shifter 81, the phase of the driving electrical signal loaded on the second electro-optic phase modulator 4 is made to satisfy... =π / 6, the total Bloch momentum of the three split optical signals are Φ1=π / 6, Φ2=5π / 6, and Φ3=3π / 2, respectively. The energy bands of the optical frequency comb before and after passing through the second electro-optic phase modulator 4 are as follows: Figure 5 As shown in (a), the transverse group velocities of the three split-beam optical signals are respectively v g1 = -aC、v g2 = -aC、v g3 = 2aC ,because v g1 = v g2 Therefore, the corresponding split optical signals propagate in the same direction and do not separate. The optical frequency comb spectrum images at different modulation depths are recorded using a spectrometer, and the results are as follows: Figure 5 As shown in (d).

[0065] The second evolution method: By adjusting the second radio frequency phase shifter 81, the phase of the driving electrical signal loaded on the second electro-optic phase modulator 4 is made to satisfy... =π / 3, the total Bloch momentum of the three split optical signals are Φ1=π / 3, Φ2=π, and Φ3=5π / 3, respectively. The energy bands of the optical frequency comb before and after passing through the second electro-optic phase modulator 4 are as follows: Figure 5 As shown in (b), the transverse group velocities of the three split-beam optical signals are respectively v g1 = - aC、v g2 = 0、v g3 = aC The optical frequency comb spectrum images at different modulation depths were recorded using a spectrometer, and the results are as follows: Figure 5 As shown in (e), the separation angle of the three beam split signals reaches its maximum at this time.

[0066] The third evolution method: By adjusting the second radio frequency phase shifter 81, the phase of the driving electrical signal loaded on the second electro-optic phase modulator 4 is made to satisfy... =π / 2, the total Bloch momentum of the three split optical signals are Φ1=π / 2, Φ2=7π / 6, and Φ3=11π / 6, respectively. The energy bands of the optical frequency comb before and after passing through the second electro-optic phase modulator 4 are as follows: Figure 5As shown in (c), the transverse group velocities of the three obtained beam split signals are respectively v g1 =0、v g2 = aC、v g3 = aC ,because v g2 = v g3 Therefore, the corresponding split optical signals propagate in the same direction and do not separate. The optical frequency comb spectrum images at different modulation depths are recorded using a spectrometer, and the results are as follows: Figure 5 As shown in (f).

[0067] Example 3: A method for controlling the self-splitting of optical signal spectrum. This embodiment is similar to Embodiment 1 above, except that a frequency multiplier 92 with n=6 is selected. In this embodiment, the frequency of the driving electrical signal loaded on the mode-locked laser 1 and the first electro-optic phase modulator 3 is 6 times the frequency of the second driving electrical signal. At this time, a photonic lattice with lattice constants of 6a and a is constructed in the frequency dimension, so that when the optical frequency comb is incident on the second electro-optic phase modulator 4, it changes from long-range coupling to near-neighbor coupling.

[0068] The first evolution method: By adjusting the second radio frequency phase shifter 81, the phase of the driving electrical signal loaded on the second electro-optic phase modulator 4 is made to satisfy... =0, the total Bloch momentum of the six split optical signals are Φ1=0, Φ2=π / 3, Φ3=2π / 3, Φ4=π, Φ5=4π / 3, and Φ6=5π / 3, respectively. The energy bands of the optical frequency comb before and after passing through the second electro-optic phase modulator 4 are as follows: Figure 6 As shown in (a), the transverse group velocities of the six split-beam optical signals are respectively v g1 =0、 v g2 =- aC , v g3 =- aC , v g4 =0、 v g5 = aC , v g6 = aC ,because v g1 = v g4 , vg2 = v g3 , v g5 = v g6 Therefore, the corresponding split optical signals propagate in the same direction and do not separate. The optical frequency comb spectrum images at different modulation depths are recorded using a spectrometer, and the results are as follows: Figure 6 As shown in (d).

[0069] The second evolution method: By adjusting the second radio frequency phase shifter 81, the phase of the driving electrical signal loaded on the second electro-optic phase modulator 4 is made to satisfy... =π / 6, the total Bloch momentum of the six split optical signals are Φ1=π / 6, Φ2=π / 2, Φ3=5π / 6, Φ4=7π / 6, Φ5=3π / 2, Φ6=11π / 6, respectively. The energy bands of the optical frequency comb before and after passing through the second electro-optic phase modulator 4 are as follows: Figure 6 As shown in (b), the transverse group velocities of the six split-beam optical signals are respectively v g1 =- aC , v g2 =-2 aC , v g3 =- aC , v g4 = aC , v g5 =2 aC , v g6 = aC ,because v g1 = v g3 , v g4 = v g6 Therefore, the corresponding split optical signals propagate in the same direction and do not separate. The optical frequency comb spectrum images at different modulation depths are recorded using a spectrometer, and the results are as follows: Figure 6 As shown in (e).

[0070] The third evolution method: By adjusting the second radio frequency phase shifter 81, the phase of the driving electrical signal loaded on the second electro-optic phase modulator 4 is made to satisfy... = The total Bloch momentum of the six split optical signals are Φ1= Φ2= +π / 3、Φ3= +2π / 3、Φ4= +π、Φ5= +4π / 3、Φ6= +5π / 3, the energy bands of the optical frequency comb before and after passing through the second electro-optic phase modulator 4 are as follows: Figure 6 As shown in (c), the transverse group velocities of the six split-beam optical signals are respectively v g1 =-6 aC / 7, v g2 =-18 aC / 7, v g3 =-12 aC / 7, v g4 =6 aC / 7, v g5 =18 aC / 7, v g6 =12 aC / 7, therefore the optical frequency comb spectra overlap. The optical frequency comb spectrum images at different modulation depths were recorded using a spectrometer, and the results are as follows: Figure 6 As shown in (f), the separation angle of the six split optical signals reaches its maximum at this time.

[0071] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for controlling the self-splitting of optical signal spectrum, characterized in that, include: S1, a light frequency comb is incident on the first electro-optic phase modulator (3) to obtain a first optical signal; the frequency interval of the light frequency comb is the same as the frequency of the driving electrical signal loaded on the first electro-optic phase modulator (3); S2, the first optical signal is input into the second electro-optic phase modulator (4) to obtain n beam-splitter optical signals; the frequency of the driving electrical signal loaded in the first electro-optic phase modulator (3) is n times the frequency of the driving electrical signal loaded in the second electro-optic phase modulator (4), and the phase of the driving electrical signal loaded in the second electro-optic phase modulator (4) satisfies: the n beam-splitter optical signals obtained by modulation by the second electro-optic phase modulator (4) respectively carry n kinds of total Bloch momentum, and the n kinds of total Bloch momentum are respectively 1= , 2= + (2π / n ), 3= + 2(2π / n ),...、 n = + ( n - 1)(2π / n ); wherein, is the total Bloch momentum of the first split light signal; n is a positive integer and is greater than 1.

2. The method of claim 1, wherein the optical signal spectrum is a broadband spectrum. n=2； The phase of the drive electrical signal of the second electro-optical phase modulator (4) also satisfies: = π / 2.

3. The method of claim 1, wherein the spectral shaping is performed by a spectral shaper. n=3； The phase of the driving electrical signal loaded on the second electro-optic phase modulator (4) also satisfies: =π / 3.

4. The method of claim 1, wherein the controlling of the optical signal spectrum beam splitting is performed by a controller. n=6； The phase of the drive electrical signal of the second electro-optical phase modulator (4) is also adapted to satisfy: = .

5. An optical signal spectrum demultiplexing device, characterized by, include: The system includes a mode-locked laser (1), a first electro-optic phase modulator (3), a second electro-optic phase modulator (4), two electro-modulation modules and an electrical signal output module (9), wherein the two electro-modulation modules are the first electro-modulation module (7) and the second electro-modulation module (8). The mode-locked laser (1), the first electro-optic phase modulator (3), and the second electro-optic phase modulator (4) are arranged sequentially along the optical path; A mode-locked laser (1) is used to provide an optical frequency comb; The first electro-optic phase modulator (3) is used to perform phase modulation on the optical frequency comb so that the optical signal generation mode transition is achieved; The second electro-optic phase modulator (4) is used to modulate the frequency and phase of the optical frequency comb emitted by the first electro-optic phase modulator (3) in order to realize the controllable beam splitting of the optical signal. The electrical signal output module (9) has three output terminals, which are respectively connected to the mode-locked laser (1), the first electro-optic phase modulator (3), and the second electro-optic phase modulator (4). The electrical signal output module (9) is used to provide driving electrical signals to the mode-locked laser (1), the first electro-optic phase modulator (3), and the second electro-optic phase modulator (4), satisfying that the frequency interval of the optical frequency comb provided by the mode-locked laser (1) is the same as the frequency of the driving electrical signal loaded on the first electro-optic phase modulator, and the frequency of the driving electrical signal loaded on the first electro-optic phase modulator (3) is n times the frequency of the driving electrical signal loaded on the second electro-optic phase modulator (4). The first electrical modulation module (7) is located between the electrical signal output module (9) and the first electro-optic phase modulator (3) and is used to adjust the amplitude and phase of the driving electrical signal entering the first electro-optic phase modulator (3); The second electrical modulation module (8) is located between the electrical signal output module (9) and the second electro-optic phase modulator (4). It is used to adjust the amplitude and phase of the driving electrical signal entering the second electro-optic phase modulator (4), so that the phase of the driving electrical signal loaded on the second electro-optic phase modulator (4) satisfies the following: the n beam splitting optical signals modulated by the second electro-optic phase modulator (4) respectively carry n kinds of total Bloch momentum, and the n kinds of total Bloch momentum are respectively 1= , 2= + (2π / n ), 3= +2(2π / n ),...、 n = + ( n - 1)(2π / n ).

6. The optical signal spectrum self-beam splitter as described in claim 5, characterized in that, The electro-modulation module includes a radio frequency amplifier, an adjustable attenuator, and a radio frequency phase shifter connected in sequence. The radio frequency amplifier and the adjustable attenuator are used to adjust the amplitude of the driving electrical signal entering the electro-optic phase modulator, and the radio frequency phase shifter is used to adjust the phase of the driving electrical signal entering the electro-optic phase modulator. The radio frequency amplifier is connected to the electrical signal output module (9), and the radio frequency phase shifter is connected to the corresponding electro-optic phase modulator.

7. The optical signal spectrum beam splitting device of claim 6, wherein, The electrical signal output module (9) includes a first power divider (91), a frequency multiplier (92), a second power divider (93), and a radio frequency signal source (94). The radio frequency signal source (94) is used to generate a sinusoidal radio frequency signal as a driving electrical signal; The second power divider (93) is connected to the radio frequency signal source (94) and is used to divide the power of the driving electrical signal output by the radio frequency signal source (94) to obtain the original frequency driving electrical signal and the second driving electrical signal; the second driving electrical signal is connected to the second electro-optic phase modulator (4) from the second output terminal. The frequency multiplier (92) is set at the first output terminal of the second power divider (93) to increase the frequency of the original frequency driving electrical signal by n times to obtain the frequency multiplier driving electrical signal; The input terminal of the first power divider (91) is connected to the output terminal of the frequency multiplier (92) to perform power distribution on the frequency multiplier drive signal to obtain the initial drive signal and the first drive signal; The initial driving electrical signal is directed to the mode-locked laser (1), and the first driving electrical signal is directed to the first electro-optic phase modulator (3).

8. The optical signal spectrum beam splitting device of claim 7, wherein, It also includes an optical frequency comb modulation module (2) located between the mode-locked laser (1) and the first electro-optic phase modulator (3); The optical frequency comb modulation module (2) includes a programmable optical filter (21) and a polarization controller (22) arranged sequentially along the optical path. The programmable optical filter (21) is used to perform Gaussian filtering on the optical frequency comb generated by the mode-locked laser (1), and the polarization controller (22) is used to adjust the polarization of the filtered optical frequency comb.

9. The optical signal spectrum beam splitting device of claim 8, wherein, It also includes an initial adjustable attenuator (6) located between the first power divider (91) and the mode-locked laser (1) for adjusting the initial drive electrical signal strength applied to the mode-locked laser (1).

10. An optical signal spectrum beam splitting device as claimed in any one of claims 5 to 9, characterized in that It also includes a spectrometer (5) located on the output side of the second electro-optic phase modulator (4) along the optical path, for detecting and recording the emitted spectrum.

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