Encrypted quantum measurement device and method based on Rydberg atoms

Abstract

The invention discloses an encrypted quantum measurement device and method based on Rydberg atoms. Atoms are excited to a Rydberg state through a beam of detection light and a beam of coupling light, and a radio signal is subjected to quantum precision measurement based on a Rydberg electromagnetic induction transparent spectrum; on the basis, the spatial light modulator is used for continuously loading spiral phases with adjustable topological charges on the detection light, time-varying encryption of measurement information is achieved, and then the time-varying encryption information is decrypted and read through the other spatial light modulator and the photoelectric detector. Compared with an existing Rydberg quantum measurement scheme, radio information is encrypted through vortex light beams, and the safety and reliability of quantum precision measurement can be effectively improved; meanwhile, the topological charge number of the loaded spiral phase is infinite theoretically, and an infinite number of permutation and combination modes are provided during quantum measurement, so that the time-varying encryption method has higher cracking difficulty.

Description

Technical Field

[0001] The present invention relates to the field of quantum sensing and measurement, and in particular to an encrypted quantum measurement device and method based on Rydberg atoms. Background Art

[0002] Rydberg atoms are highly excited atoms with a large principal quantum number, and are generally excited by cesium or rubidium atoms. Rydberg atoms have some characteristics that other atoms do not have, such as a large orbital radius, a long radiation lifetime, and a strong electric dipole moment, which makes them very sensitive to external electric fields and can be used for quantum precision measurement of radio signals. Therefore, Rydberg atoms have very important application value in the field of quantum information.

[0003] In the prior art, radio precision measurement technology based on Rydberg atoms generally adopts an optical measurement method, including a beam of detection light and a beam of coupling light. First, alkali metal atomic vapor is encapsulated in an atomic gas chamber, and the detection light and coupling light are incident on the atomic gas chamber at the same time. Among them, the detection light and coupling light overlap in the atomic gas chamber, but the transmission directions are opposite to each other, so as to reduce the influence of the Doppler effect on the measurement accuracy. By adjusting the frequency of the detection light and coupling light to be equal to the resonant frequency of the atomic specific energy level transition, the ground state atom is excited to the Rydberg state. When scanning the detection light or coupling light, the Rydberg electromagnetically induced transparency spectrum can be obtained through the photodetector. When the radio signal acts on the Rydberg atoms in the atomic gas chamber, the electromagnetically induced transparency spectrum will change: (1) For resonant radio signals, the electromagnetically induced transparency spectrum will show the Autler-Townes splitting effect, and the splitting width is proportional to the radio electric field strength, thereby realizing quantum measurement; (2) For non-resonant radio signals, the electromagnetically induced transparency spectrum will produce a Stark frequency shift, and its frequency shift amount is proportional to the square of the external electric field strength, thereby realizing radio signal measurement.

[0004] However, the above-mentioned existing quantum measurement technology of radio signals based on Rydberg atoms is a non-encrypted technology. It is very easy to directly read radio information by obtaining the electromagnetically induced transparent spectrum of lasers, causing leakage of sensitive information and failing to guarantee the security and reliability of communications. Summary of the invention

[0005] In order to solve the problems existing in the prior art, the present invention provides an encrypted quantum measurement device and method based on Rydberg atoms, which are used to improve the security and reliability of information transmission and reduce the risk of information leakage existing in the prior art.

[0006] To achieve the above object, the present invention adopts the following scheme:

[0007] The present invention provides an encrypted quantum measurement device based on Rydberg atoms, comprising a detection light laser, a coupling light laser, a first dichroic mirror, a second dichroic mirror, a photodetector, an atomic gas chamber, a computer, and a spatial light encryption modulator and a spatial light decryption modulator, wherein the detection light laser is fixed at one end of the device to generate a beam of detection light, which passes through the spatial light encryption modulator, the first dichroic mirror, the atomic gas chamber, the second dichroic mirror, and the spatial light decryption modulator in sequence to reach the photodetector; the coupling light laser is arranged below the second dichroic mirror to generate a beam of coupling light, which passes through the second dichroic mirror and the atomic gas chamber in sequence to reach the first dichroic mirror; the detection light and the coupling light overlap in the atomic gas chamber, and the transmission directions are opposite; the spatial light encryption modulator, the spatial light decryption modulator, and the photodetector are electrically connected to the computer.

[0008] In some embodiments, the atomic gas cell encapsulates cesium atomic vapor.

[0009] In some embodiments, the computer is one or more. When the computer is multiple, different computers control the spatial light encryption modulator and the spatial light decryption modulator respectively.

[0010] In some embodiments, the spatial light encryption modulator and the spatial light decryption modulator modulate light using a spiral phase hologram whose topological charge varies with time.

[0011] The present invention also provides an encrypted quantum measurement method based on Rydberg atoms, based on the above-mentioned encrypted quantum measurement device based on Rydberg atoms, comprising the following steps:

[0012] S1: Encapsulating cesium atomic vapor in the atomic gas chamber;

[0013] S2: by adjusting the wavelength of the detection light, the cesium atoms in the atomic gas chamber are excited from the ground state to the intermediate state;

[0014] S3: by adjusting the wavelength of the coupling light, the cesium atoms in the atomic gas cell are further excited from the intermediate state to the Rydberg state;

[0015] S4: the first dichroic mirror and the second dichroic mirror reflect the coupling light and transmit the detection light at the same time, so that the detection light and the coupling light overlap in the atomic gas chamber and have opposite transmission directions;

[0016] S5: the computer loads a spiral phase hologram whose topological charge varies with time into the spatial light encryption modulator, and modulates the detection light from a Gaussian beam to a vortex beam;

[0017] S6: the computer loads a spiral phase hologram in the spatial light decryption modulator, whose topological charge is opposite to that of the spiral phase hologram in the spatial light encryption modulator in step S5, and modulates the detection light modulated in step S5 from a vortex beam to a Gaussian beam;

[0018] S7: applying the radio signal to be tested to the atoms in the atomic gas chamber;

[0019] S8: The photodetector converts the optical signal into an electronic signal output, measures the Rydberg electromagnetic induction transparency spectrum of the detection light, and measures the radio signal to be tested.

[0020] In some embodiments, the computer continuously changes the spiral phase hologram in the spatial light encryption modulator to perform time-varying encryption on the measurement information.

[0021] The beneficial effects of the present invention are:

[0022] (1) The encrypted quantum measurement device and method based on Rydberg atoms proposed in the present invention encrypts the measurement information through a vortex beam, which can effectively improve the security and reliability of quantum measurement compared with the traditional Gaussian beam measurement;

[0023] (2) The topological charge of the spiral phase hologram used in the Rydberg atom-based encrypted quantum measurement device and method of the present invention is theoretically infinite, and has infinite permutations and combinations during quantum measurement, so its time-varying encryption method has a higher degree of cracking difficulty;

[0024] (3) The encrypted quantum measurement device based on Rydberg atoms described in the present invention has a simple structure, so that its volume can be miniaturized and integrated. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Schematic diagram of the optical path of the encrypted quantum measurement device based on Rydberg atoms in an embodiment of the present invention;

[0026] Figure 2-3 Schematic diagram of the principle of the encrypted quantum measurement method based on Rydberg atoms in an embodiment of the present invention.

[0027] In the figure, 1- detection light laser; 2- spatial light encryption modulator; 3- first dichroic mirror; 4- atomic gas chamber; 5- second dichroic mirror; 6- spatial light decryption modulator; 7- photodetector; 8- coupled light laser; 9- computer. DETAILED DESCRIPTION

[0028] In order to make the technical solutions and advantages of the present invention clearer, the technical solutions of the embodiments of the present invention will be fully described below in conjunction with the drawings in the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0030] The present invention provides an encrypted quantum measurement device and method based on Rydberg atoms, wherein the device is as follows: Figure 1 As shown, it includes: a detection light laser 1, a spatial light encryption modulator 2, a first dichroic mirror 3, an atomic gas chamber 4, a second dichroic mirror 5, a spatial light decryption modulator 6, a photodetector 7, a coupling light laser 8, and a computer 9; the atomic gas chamber encapsulates cesium atomic vapor; the detection light laser is fixed at one end of the device, and along the detection light are the spatial light encryption modulator, the first dichroic mirror, the atomic gas chamber, the second dichroic mirror, the spatial light decryption modulator, and the photodetector; the coupling light laser is fixed below the second dichroic mirror, and along the coupling light are the second dichroic mirror, the atomic gas chamber, and the first dichroic mirror; the spatial light encryption modulator, the spatial light decryption modulator, and the photodetector are electrically connected to the computer.

[0031] like Figure 2-3As shown, the detection light laser generates a beam of detection light and injects it into the atomic gas chamber, and the detection light is a Gaussian beam; the coupling light laser generates a beam of coupling light, and the first dichroic mirror is used to make the coupling light coincide with the detection light in the atomic gas chamber, and the transmission direction is opposite; the atomic gas chamber is used as a quantum measurement probe, and the radio signal to be measured acts on the atoms in the atomic gas chamber. By adjusting the wavelengths of the detection light and the coupling light, the cesium atoms in the atomic gas chamber are excited to the Rydberg state, and the radio information is transmitted to the detection light based on the Rydberg atoms. At this time, the photodetector can obtain the electromagnetically induced transparent spectrum of the detection light and perform unencrypted measurement of the radio signal; a computer is used in a spatial optical encryption modulator A spiral phase hologram is loaded in the spatial light decryption modulator, and the Gaussian detection light is modulated into a vortex detection light, and its topological charge (m1) is controlled by a computer; the vortex detection light passes through the atomic gas chamber, and the measurement information is encrypted by the loaded spiral phase, and the photodetector cannot directly read the measurement information at this time; a spiral phase hologram with a topological charge (m2) opposite to that of the spatial light encryption modulator is loaded in the spatial light decryption modulator by a computer, and the vortex detection light is modulated into a Gaussian detection light, and the encrypted information is decrypted, and the photodetector can read the measurement information at this time; the spiral phase hologram in the spatial light encryption modulator is continuously changed by a computer to perform time-varying encryption on the measurement information.

[0032] In some embodiments, there are multiple computers, and the spatial light encryption modulator and the spatial light decryption modulator are controlled by different computers, respectively, so as to facilitate flexible deployment of the transmitting end and the receiving end.

[0033] In some embodiments, the present invention further provides an encrypted quantum measurement method based on Rydberg atoms, based on the above-mentioned encrypted quantum measurement device based on Rydberg atoms, comprising the following steps:

[0034] S1: Encapsulating cesium atomic vapor in the atomic gas chamber;

[0035] S2: by adjusting the wavelength of the detection light, the cesium atoms in the atomic gas chamber are excited from the ground state to the intermediate state;

[0036] S3: by adjusting the wavelength of the coupling light, the cesium atoms in the atomic gas cell are further excited from the intermediate state to the Rydberg state;

[0037] S4: the first dichroic mirror and the second dichroic mirror reflect the coupling light and transmit the detection light at the same time, so that the detection light and the coupling light overlap in the atomic gas chamber and have opposite transmission directions;

[0038] S5: the computer loads a spiral phase hologram whose topological charge varies with time into the spatial light encryption modulator, and modulates the detection light from a Gaussian beam to a vortex beam;

[0039] S6: the computer loads a spiral phase hologram in the spatial light decryption modulator, whose topological charge is opposite to that of the spiral phase hologram in the spatial light encryption modulator in step S5, and modulates the detection light modulated in step S5 from a vortex beam to a Gaussian beam;

[0040] S7: applying the radio signal to be tested to the atoms in the atomic gas chamber;

[0041] S8: The photodetector converts the optical signal into an electronic signal output, measures the Rydberg electromagnetic induction transparency spectrum of the detection light, and measures the radio signal to be tested.

[0042] like Figure 3 , the schematic diagram of the device proposed by the present invention at four points A, B, C, and D is shown in the figure. It can be seen that the encryption effect of the scheme of the present invention is good. In an unknown encryption mode, the correct signal cannot be obtained, and after decryption, the radio signal information can be obtained.

[0043] In the description of this specification, reference to the terms "one embodiment" and "example" means that the specific features, structures or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the combination in a suitable manner in the relative embodiment or example.

[0044] It must be pointed out that the description of the above embodiments is not intended to be limiting but only to help understand the core idea of ​​the present invention. For ordinary technicians in this technical field, any improvements to the present invention and alternatives equivalent to the product, without departing from the principles of the present invention, also fall within the scope of protection of the claims of the present invention.

Claims

1. An encrypted quantum measurement device based on Rydberg atoms, comprising a detection light laser, a coupling light laser, a first dichroic mirror, a second dichroic mirror, a photodetector, an atomic gas chamber, and a computer. It is characterized in that It also includes a spatial light encryption modulator and a spatial light decryption modulator, wherein the detection light laser is fixed at one end of the device to generate a beam of detection light, which passes through the spatial light encryption modulator, the first dichroic mirror, the atomic gas chamber, the second dichroic mirror, and the spatial light decryption modulator in sequence to reach the photodetector; the coupling light laser is arranged below the second dichroic mirror to generate a beam of coupling light, which passes through the second dichroic mirror and the atomic gas chamber in sequence to reach the first dichroic mirror; the detection light and the coupling light overlap in the atomic gas chamber, and the transmission directions are opposite; the spatial light encryption modulator, the spatial light decryption modulator, and the photodetector are electrically connected to a computer.

2. The encrypted quantum measurement device based on Rydberg atoms according to claim 1, It is characterized in that The atomic gas cell encapsulates cesium atomic vapor.

3. The encrypted quantum measurement device based on Rydberg atoms according to claim 1, It is characterized in that There are one or more computers. When there are multiple computers, different computers respectively control the spatial light encryption modulator and the spatial light decryption modulator.

4. The encrypted quantum measurement device based on Rydberg atoms according to claim 1, It is characterized in that The spatial light encryption modulator and the spatial light decryption modulator use a spiral phase hologram whose topological charge varies with time to modulate light.

5. A method of encrypted quantum measurement based on Rydberg atoms, It is characterized in that The encrypted quantum measurement device based on Rydberg atoms according to any one of claims 1 to 4 comprises the following steps: S1: Encapsulating cesium atomic vapor in the atomic gas chamber; S2: by adjusting the wavelength of the detection light, the cesium atoms in the atomic gas chamber are excited from the ground state to the intermediate state; S3: by adjusting the wavelength of the coupling light, the cesium atoms in the atomic gas cell are further excited from the intermediate state to the Rydberg state; S4: the first dichroic mirror and the second dichroic mirror reflect the coupling light and transmit the detection light at the same time, so that the detection light and the coupling light overlap in the atomic gas chamber and have opposite transmission directions; S5: the computer loads a spiral phase hologram whose topological charge varies with time into the spatial light encryption modulator, and modulates the detection light from a Gaussian beam to a vortex beam; S6: the computer loads a spiral phase hologram in the spatial light decryption modulator, whose topological charge is opposite to that of the spiral phase hologram in the spatial light encryption modulator in step S5, and modulates the detection light modulated in step S5 from a vortex beam to a Gaussian beam; S7: applying the radio signal to be tested to the atoms in the atomic gas chamber; S8: The photodetector converts the optical signal into an electronic signal output, measures the Rydberg electromagnetic induction transparency spectrum of the detection light, and measures the radio signal to be tested.

6. The method according to claim 5, It is characterized in that The computer continuously changes the spiral phase hologram in the spatial light encryption modulator to perform time-varying encryption on the measurement information.

Images