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CN-116430598-B - Array photon orbital angular momentum beam quantum regulation and control system based on phase screen

CN116430598BCN 116430598 BCN116430598 BCN 116430598BCN-116430598-B

Abstract

The invention discloses an array photon orbital angular momentum beam quantum regulation and control system based on a phase screen, belongs to the technical field of quantum regulation and control, and aims to solve the problem of mutual overlapping interference between sub-beams of existing array photon orbital angular momentum beams. The method comprises the steps of laser, a beam shaping unit, a polarization regulating unit and a quantum state regulating unit, wherein the beam shaping unit is used for spatially filtering and expanding laser beams generated by the laser to generate parallel beams, the polarization regulating unit is used for regulating and controlling the polarization of the parallel beams output by the beam shaping unit to generate linearly polarized beams in a horizontal polarization state, the quantum state regulating unit is used for regulating and controlling the array photon orbital angular momentum of the linearly polarized beams to obtain array photon orbital angular momentum beams, each sub beam in the array is independent, and the array photon orbital angular momentum beams with independent sub beams can be generated through compact light paths by utilizing the method.

Inventors

  • ZHANG ZIJING
  • CEN LONGZHU
  • ZHAO YUAN
  • Cui Chengshuai

Assignees

  • 哈尔滨工业大学

Dates

Publication Date
20260512
Application Date
20230420

Claims (6)

  1. 1. The array photon orbital angular momentum beam quantum regulation and control system based on the phase screen is characterized by comprising a laser (1), a beam shaping unit, a polarization regulation and control unit and a quantum state regulation and control unit; the beam shaping unit is used for spatially filtering and expanding the laser beam generated by the laser (1) to generate a parallel beam; the polarization regulation and control unit is used for regulating and controlling the polarization of the parallel light beams output by the light beam shaping unit to generate linearly polarized light beams in a horizontal polarization state; The quantum state regulating and controlling unit is used for regulating and controlling the array photon orbital angular momentum of the linearly polarized light beam to obtain an array photon orbital angular momentum light beam, and each sub light beam in the array is independent; The quantum state regulation and control unit comprises a spatial light modulator (7) and a computer (8), and the quantum state regulation and control process comprises the following steps: The computer (8) regulates and controls the incident laser quantum state by controlling the phase screen loaded on the spatial light modulator (7), and the complex amplitude transmittance of the phase screen meets the following conditions: Wherein T is complex amplitude transmittance, rect is a rectangular function; There is a relation Wherein the method comprises the steps of Representing any two adjacent unit vectors which are mutually perpendicular, namely, any two adjacent unit vectors of a phase screen loaded on a spatial light modulator are mutually perpendicular, and a is Is a mold of (2); x and y are the abscissa and ordinate of a rectangular coordinate system of each point on the phase screen, exp is an e exponential function, i is an imaginary unit, l is the photon orbital angular momentum order of the phase screen, and phi is the polar coordinate system azimuth angle of the photon orbital angular momentum light field of the phase screen; c (n 1 ,n 2 ) is the sum coefficient, according to Solving, wherein n 1 is a row coefficient of the array photon orbital angular momentum, n 2 is a column coefficient of the array photon orbital angular momentum, and integers are taken; delta (x) delta is delta function.
  2. 2. The array photon orbital angular momentum beam quantum regulation system based on the phase screen according to claim 1, wherein the beam shaping unit comprises a short focal lens (2), a small aperture diaphragm (3) and a long focal lens (4); the back focal plane of the short-focus lens (2) is overlapped with the front focal plane of the long-focus lens (4), the aperture diaphragm (3) is positioned on the overlapped focal plane, the laser beam is focused at the clear aperture of the aperture diaphragm (3) through the short-focus lens (2), and the transmitted light is condensed into a parallel beam through the long-focus lens (4).
  3. 3. The array photon orbital angular momentum beam quantum regulation system based on the phase screen according to claim 2, wherein the beam shaping unit expands the incident laser beam by f2/f1 times, wherein f1 is a short focal lens focal length, f2 is a long focal lens focal length, and the expanded laser irradiates the spatial light modulator (7) with an approximate plane wave.
  4. 4. The array photon orbital angular momentum beam quantum regulation system based on the phase screen according to claim 1, wherein the polarization regulation unit comprises a linear polarizer (5) and a half wave plate (6); the linear polarizing plate (5) modulates the incident laser light into linear polarized light, and then the half wave plate (6) modulates the polarization direction of the incident linear polarized light into a horizontal direction, so as to generate the linear polarized light in the horizontal polarization state.
  5. 5. The phase screen-based array photon orbital angular momentum beam quantum regulation system according to claim 4, wherein an included angle between a fast axis direction of the half wave plate (6) and a polarizing direction of the linear polarizer (5) is equal to an included angle between the half wave plate (6) and a horizontal direction of the fast axis direction.
  6. 6. The array photon orbital angular momentum beam quantum regulation and control system based on the phase screen according to claim 1, wherein the spatial light modulator (7) is a phase controller based on the anisotropy of liquid crystal molecules, and the phase regulation and control direction is a horizontal direction.

Description

Array photon orbital angular momentum beam quantum regulation and control system based on phase screen Technical Field The invention relates to an anti-interference modulation technology of array photon orbital angular momentum beams, which modulates independent sub-beams which are not overlapped with each other, and belongs to the technical field of quantum regulation and control. Background Photon orbital angular momentum light beam is a light field with spiral phase structure and is widely applied in the fields of optical communication, optical operation and active laser detection. The array photon orbital angular momentum beam can be used for array illumination, and two-dimensional array control and anti-cloud three-dimensional laser imaging are realized. The existing array photon orbit angular momentum beam generation method comprises an interference method, a spiral phase space filtering method, a hollow multimode waveguide method and the like. The sub-beams generated by the method are mutually overlapped and interfered, which is not beneficial to the application requiring discrete lattice illumination. Thus, in order to address the above shortcomings, it is desirable to provide an array of photon orbital angular momentum beams, wherein the sub-beams in the array are independent of each other and do not overlap. Disclosure of Invention Aiming at the problem of mutual overlapping interference among sub-beams of the existing array photon orbital angular momentum beams, the invention provides an array photon orbital angular momentum beam quantum regulation and control system based on a phase screen. The invention relates to a phase screen-based array photon orbital angular momentum beam quantum regulation and control system, which comprises a laser 1, a beam shaping unit, a polarization regulation and control unit and a quantum state regulation and control unit; the beam shaping unit is used for spatially filtering and expanding the laser beam generated by the laser 1 to generate a parallel beam; the polarization regulation and control unit is used for regulating and controlling the polarization of the parallel light beams output by the light beam shaping unit to generate linearly polarized light beams in a horizontal polarization state; The quantum state regulating and controlling unit is used for regulating and controlling the array photon orbital angular momentum of the linearly polarized light beam to obtain an array photon orbital angular momentum light beam, and each sub light beam in the array is independent; The quantum state regulation and control unit comprises a spatial light modulator 7 and a computer 8, and the quantum state regulation and control process comprises the following steps: The computer 8 regulates and controls the incident laser quantum state by controlling a phase screen loaded on the spatial light modulator 7, and the complex amplitude transmittance of the phase screen meets the following conditions: Wherein T is complex amplitude transmittance, rect is a rectangular function; There is a relation Wherein the method comprises the steps ofRepresenting any two adjacent unit vectors which are mutually perpendicular, namely, any two adjacent unit vectors of a phase screen loaded on a spatial light modulator are mutually perpendicular, and a isIs a mold of (2); x and y are the abscissa and ordinate of a rectangular coordinate system of each point on the phase screen, exp is an e exponential function, i is an imaginary unit, l is the photon orbital angular momentum order of the phase screen, and phi is the polar coordinate system azimuth angle of the photon orbital angular momentum light field of the phase screen; c (n 1,n2) is the sum coefficient, according to Solving, wherein n 1 is a row coefficient of the array photon orbital angular momentum, n 2 is a column coefficient of the array photon orbital angular momentum, and integers are taken; delta (x) delta is delta function. Preferably, the beam shaping unit comprises a short focal lens 2, an aperture stop 3 and a long focal lens 4; The back focal plane of the short-focus lens 2 is coincident with the front focal plane of the long-focus lens 4, the aperture diaphragm 3 is positioned on the coincident focal plane, the laser beam is focused at the clear aperture of the aperture diaphragm 3 through the short-focus lens 2, and the transmitted light is condensed into a parallel beam through the long-focus lens 4. Preferably, the beam shaping unit expands the incident laser beam by a factor of f2/f 1. Where f1 is the short focal lens focal length and f2 is the long focal lens focal length. The expanded laser light irradiates the spatial light modulator 7 with an approximately plane wave. Preferably, the polarization controlling unit includes a linear polarizer 5 and a half wave plate 6; The linear polarizer 5 modulates the incident laser light into linear polarized light, and then the half wave plate 6 modulates the polarization directi