A broadband atomic terahertz detection method and device

Abstract

This invention provides a broadband atomic terahertz detection method and apparatus, relating to the field of terahertz detection and imaging technology. The method includes: generating a time-coded sequence using an arbitrary waveform generator; controlling a microwave switch to perform orthogonal coding modulation on a terahertz field to generate a terahertz differential signal carrying coded information; applying the terahertz differential signal to Rydberg atoms in an atomic gas cell to convert terahertz information into changes in the transmitted light intensity of the probe light, and converting the optical signal into an electrical signal; synchronously demodulating and acquiring the electrical signal to generate a measurement vector; and reconstructing the original terahertz time-domain waveform from the measurement vector using a compressed sensing reconstruction algorithm. This invention, by combining superheterodyne detection and time-domain computational imaging algorithms, overcomes the physical limitations of the bandwidth of atomic detectors, achieving rapid and high-resolution detection of broadband terahertz signals while maintaining their high sensitivity advantages.

Description

Technical Field

[0001] This invention relates to the field of terahertz detection and imaging technology, and in particular to a broadband atomic terahertz detection method and apparatus. Background Technology

[0002] Terahertz waves generally refer to electromagnetic radiation with frequencies ranging from 0.1 to 10 terahertz (THz), whose spectral position lies between microwaves and infrared light. This band possesses many unique properties, such as excellent penetration through many non-polar materials (e.g., paper, plastics, and fabrics), low photon energy that does not cause ionizing damage to biological tissues like X-rays, and the fact that many molecular rotational or vibrational energy levels lie in this band. This makes terahertz technology demonstrate enormous application potential in fields such as non-destructive testing, materials spectral analysis, biomedical imaging, security inspection, and next-generation high-speed secure communications.

[0003] However, the rapid development and practical application of terahertz technology have long been constrained by the lack of efficient, sensitive, and broadband detection methods. Existing terahertz detection technologies are mainly divided into two categories, both of which have significant limitations:

[0004] The first category is coherent detection techniques based on photoconductive antennas or nonlinear crystals (such as ZnTe). These techniques typically require femtosecond laser pulses as both pump and probe sources, reconstructing the terahertz time-domain waveform by measuring changes in photocurrent or optical polarization state induced by the terahertz electric field. While they offer high time resolution and enable time-domain spectral measurements, the entire system relies on expensive and complex femtosecond lasers, resulting in large size. Furthermore, their effective detection bandwidth is often limited by the laser pulse width, the antenna's frequency response, or the crystal's phase-matching conditions, making it difficult to cover a wider continuous terahertz spectrum.

[0005] The second category is incoherent detectors, mainly including pyroelectric detectors, calorimeters, and Gaussian cells. These detectors operate by sensing the temperature rise or other thermal effects caused by terahertz radiation. Their advantage lies in their relatively simple structure, and some can operate at room temperature. However, their inherent disadvantages are that their sensitivity is usually low, their response speed is slow (on the order of milliseconds), making it difficult to effectively detect rapidly changing transient terahertz signals or achieve high-speed imaging. Their signal-to-noise ratio and dynamic range are also often limited.

[0006] In recent years, quantum sensing technology based on Rydberg atoms at room temperature has provided a revolutionary new approach for terahertz detection. Rydberg atoms are extremely sensitive to external electric fields, and highly sensitive electric field measurements can be achieved through atomic superheterodyne detection technology. However, the response bandwidth of such atomic detectors is inherently limited by the natural linewidth and coherence time of the atomic energy levels, resulting in a narrow instantaneous bandwidth. This severely restricts their ability to directly detect broadband or rapidly time-varying terahertz signals. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide a broadband atomic terahertz detection method and device. The device combines superheterodyne detection technology with time-domain computational imaging algorithm to overcome the physical limitation of the bandwidth of the atomic detector itself, and achieves fast and high-resolution detection of broadband terahertz signals while maintaining its high sensitivity advantage.

[0008] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:

[0009] In a first aspect, a broadband atomic terahertz detection method is provided, the method comprising:

[0010] Step 1: Use an arbitrary waveform generator to generate a time-coded sequence, control a microwave switch to perform orthogonal coding modulation on the terahertz field, and generate a terahertz differential signal carrying coded information by the interaction between the terahertz signal field and the local oscillator field.

[0011] Step 2: Apply the terahertz differential signal to the Rydberg atoms in the atomic gas cell to convert the terahertz information into changes in the transmitted light intensity of the probe light, and convert the optical signal into an electrical signal.

[0012] Step 3: Synchronously demodulate and acquire the electrical signal to generate a measurement vector, and reconstruct the original terahertz time-domain waveform from the measurement vector using a compressed sensing reconstruction algorithm.

[0013] Generating a terahertz differential signal carrying coded information specifically includes:

[0014] The generated specific time encoding matrix is ​​input into the arbitrary waveform generator, and the time encoding matrix has orthogonality and binaryity;

[0015] The microwave switch is driven by the arbitrary waveform generator to perform orthogonal coding modulation on the terahertz signal according to the coding sequence of each row of the time coding matrix, so as to generate the terahertz differential signal.

[0016] Furthermore, the terahertz information is converted into changes in the transmitted light intensity of the probe light, specifically including:

[0017] Alkali metal atoms were prepared to the Rydberg state by irradiating an atomic gas cell in a collinear manner with a probe laser and a coupling laser.

[0018] By locking the frequencies of the probe laser and the coupling laser to specific atomic energy level transitions, an electromagnetically induced transparency effect is formed in the atomic gas cell, and the EIT transmission peak of the probe light is obtained.

[0019] The terahertz differential signal carrying the encoded information interacts with the atoms in the Rydberg state. The energy of the terahertz photon resonates with the atomic energy level and causes the atomic energy level to transition. The EIT transmission peak is modulated by the change of quantum state, thereby converting the terahertz information into the change of the transmitted light intensity of the probe light.

[0020] A balanced photodetector is used to receive the probe laser carrying terahertz information emitted from the atomic gas chamber and convert the optical signal into an electrical signal.

[0021] Furthermore, the electrical signal is synchronously demodulated and acquired to reconstruct the original terahertz time-domain waveform, specifically including:

[0022] The electrical signal is demodulated and acquired using a lock-in amplifier, and the signal is preprocessed by differential and integral operations using computer code to generate a measurement vector.

[0023] The compressed sensing reconstruction algorithm is used to process the measurement vector to reconstruct the original terahertz time-domain signal with high fidelity using fewer measurements than the Nyquist sampling rate.

[0024] A noise reduction algorithm is used to optimize the reconstructed time-domain signal.

[0025] Furthermore, during the generation of terahertz differential signals and data demodulation and acquisition after encoding and modulating the terahertz waves, an external signal source is used to externally synchronize the arbitrary waveform generator and the lock-in amplifier to maintain hardware synchronization. The lock-in amplifier synchronously integrates the demodulated signal within a fixed integration time window for each line of time encoding to obtain the corresponding measurement value.

[0026] Secondly, a broadband atom terahertz detection device is provided for implementing the aforementioned broadband atom terahertz detection method, the device comprising:

[0027] The terahertz modulation module is used to perform orthogonal coding modulation on the terahertz field using a time-coded sequence to generate a terahertz differential signal carrying coded information. It includes:

[0028] An arbitrary waveform generator is used to generate the time-coded sequence;

[0029] A microwave source outputs a fundamental frequency microwave, which is multiplied by a terahertz frequency multiplier to generate a terahertz signal; its output terminal is connected to the signal input terminal of the microwave switch, and after being modulated by the microwave switch, it outputs a terahertz signal carrying modulation information through a terahertz frequency multiplier.

[0030] A microwave switch, the control terminal of which is connected to the output terminal of the arbitrary waveform generator, is driven by the time-coded sequence;

[0031] A terahertz frequency multiplier multiplies the fundamental frequency microwave output from a microwave source to obtain a terahertz signal.

[0032] A signal detection module, used to convert the information carried by the terahertz differential signal into an electrical signal, includes:

[0033] A pump laser and a probe laser are used to emit a coupling laser and a probe laser, respectively. The frequencies of the probe laser and the coupling laser are locked and then collinearly irradiate the atomic gas cell to prepare atoms to the Rydberg state.

[0034] The atomic gas chamber is filled with alkali metal atomic vapor. Its main function is to convert the received terahertz differential signal into the transmitted light intensity signal of the probe light.

[0035] A photodetector is disposed in the transmission optical path of the detection laser to receive changes in the intensity of the transmitted light and convert them into electrical signals.

[0036] Thirdly, a computing device includes:

[0037] One or more processors;

[0038] A storage device for storing one or more programs that, when executed by one or more processors, cause the one or more processors to implement the method.

[0039] Fourthly, a computer-readable storage medium storing a program that, when executed by a processor, implements the method.

[0040] The above-described solution of the present invention has at least the following beneficial effects:

[0041] This invention rapidly modulates a terahertz field using a time-coded sequence, loading the high-frequency (terahertz band) target signal information onto a low-frequency modulation envelope. The subsequent atomic detection and phase-locked demodulation processes primarily respond to this low-frequency modulation signal, rather than directly to the terahertz carrier frequency. Therefore, the system's final effective detection bandwidth is no longer limited by the narrow linewidth of the atomic energy level or the physical bandwidth of the photodetector, but is determined by the modulation speed (microwave switching), the response time of the atomic system, and the capabilities of the reconstruction algorithm. This achieves a leap from the megahertz bandwidth of traditional atomic detectors to gigahertz or even higher effective bandwidths.

[0042] Traditional atomic spectroscopy requires slowly scanning the frequency of a laser or terahertz source to obtain spectral information, which is time-consuming and cannot capture transient signals. Combining atomic superheterodyne detection with computational imaging allows for the direct reconstruction of complete terahertz time-domain waveforms. This method greatly improves sampling and detection speed, making it possible to observe non-repeatable, rapidly changing terahertz transient phenomena (such as ultrashort pulses and transient spectra), providing unprecedented time resolution.

[0043] By employing an orthogonal time-coding matrix and differential measurement technology, the signal can be effectively separated from common-mode noise (such as laser intensity noise and environmental electromagnetic interference), thus improving the system's anti-interference capability from the measurement principle. Secondly, the quantum advantage of the Rydberg atom's extremely high sensitivity to electric fields (down to the microvolt per centimeter level) is fully preserved. Finally, the compressed sensing algorithm can still reconstruct the signal with high fidelity from noisy data at a sampling rate lower than the Nyquist rate, further extracting effective information from the data. The combination of these three factors achieves high signal-to-noise ratio and high sensitivity detection performance.

[0044] The inherent compatibility between the time coding matrix and compressed sensing algorithms enables the system to fully recover the signal from far fewer measurements than traditional methods. This not only reduces data acquisition time but also alleviates the pressure on hardware speed and data storage. The core components of the system (such as microwave switches, lasers, and lock-in amplifiers) are all mature commercial equipment, which improves the system's reliability, integrability, and practical application prospects while maintaining high performance.

[0045] Based on the reconstructed high-fidelity time-domain waveform, spectral information can be directly obtained through Fourier transform to achieve broadband spectral analysis. By combining spatial scanning or array-based detection schemes, this method can be extended to fast terahertz imaging, providing a powerful new tool for applications such as non-destructive testing of materials and biological tissue imaging. Attached Figure Description

[0046] Figure 1 This is a flowchart of a broadband atomic terahertz detection method according to the present invention;

[0047] Label Explanation:

[0048] Figure 1 In Chinese: I - Terahertz modulation module, II - Signal detection module, III - Data acquisition and processing module.

[0049] 1-Arbitrary waveform generator, 2-Microwave source, 3-Microwave switch, 4-Terahertz frequency multiplier, 5-Atomic gas cell, 6-Photodetector, 7-Computer. Detailed Implementation

[0050] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0051] like Figure 1 As shown, this embodiment discloses a broadband atomic terahertz detection method, including the following steps:

[0052] Step 101: Use an arbitrary waveform generator to generate a time-coded sequence, control a microwave switch to perform orthogonal coding modulation on the terahertz field, so that the signal field interacts with the local oscillator field to generate a terahertz differential signal carrying coded information;

[0053] Step 102: Input the terahertz differential signal into the atomic gas cell, act on the Rydberg atoms inside, and convert the terahertz information into changes in the transmitted light intensity of the probe light through atomic energy level transitions, and use a photodetector to convert the optical signal into an electrical signal.

[0054] Step 103: The electrical signal is synchronously demodulated and acquired using a lock-in amplifier. After differential and integral preprocessing, a measurement vector is generated. The original terahertz time-domain waveform or spectrum is reconstructed from the measurement vector with high fidelity using a compressed sensing reconstruction algorithm. The reconstruction result is then optimized using a noise reduction algorithm.

[0055] Furthermore, step 101 specifically includes:

[0056] To improve the signal-to-noise ratio and sampling efficiency, the modulation module employs terahertz time-coded matrix encoding technology, which enables orthogonal encoding and decoding of signals. Specifically, a specific time-coded input is generated and fed into an arbitrary waveform generator. Each row of the coded sequence drives a microwave switch via the arbitrary waveform generator to orthogonally encode and modulate the terahertz signal. The time-coded matrix exhibits excellent orthogonality and binaryity, and is compatible with compressed sensing algorithms, offering significant advantages.

[0057] Furthermore, step 102 specifically includes:

[0058] A probe laser and a coupling laser collinearly irradiate an atomic gas cell, preparing alkali metal atoms to the Rydberg state (|r>). The probe laser frequency is locked to the transition from the ground state (|g>) to the intermediate state (|e>), while the coupling laser frequency corresponds to the transition from |e> to |r>. When both lasers act simultaneously and satisfy the two-photon resonance condition, the system exhibits an electromagnetically induced transparency effect, significantly increasing the probe light transmittance and forming an EIT transmission peak. The terahertz differential signal carrying encoded information incident on the atomic gas cell interacts with the Rydberg atoms, converting the terahertz information into changes in the transmitted light intensity of the probe light through atomic energy level transitions. A photodetector then converts this optical signal into an electrical signal.

[0059] Furthermore, step 103 specifically includes:

[0060] The superheterodyne signal data, demodulated and acquired using a lock-in amplifier, is subjected to differential measurement and integration to generate a measurement vector. This is a crucial preprocessing step for suppressing noise and improving the signal-to-noise ratio. Subsequently, a compressed sensing reconstruction algorithm is used to reconstruct the signal from the measurement vector, enabling high-fidelity reconstruction of the time-domain signal with a number of measurements far lower than the Nyquist sampling rate. Finally, a nonlocal mean denoising algorithm is used for post-processing of the reconstructed signal to further suppress residual noise.

[0061] Furthermore, step 103 includes the following:

[0062] During the execution of steps 101 and 103, the arbitrary waveform generator and the lock-in amplifier maintain hardware synchronization; for each line of time-coded lock-in amplifier, the demodulated signal is synchronously integrated within a fixed integration time window to obtain the corresponding measurement value, so as to ensure the accuracy of the measurement vector.

[0063] A broadband atomic terahertz detection device, in a preferred embodiment, such as Figure 1 As shown, it includes the following steps:

[0064] Turn on the relevant experimental equipment, complete laser frequency locking, and set the relevant experimental parameters. Generate an n-order time-coding matrix in the computer and perform differential processing, converting each row of the matrix into a waveform file sequentially. +1 corresponds to a 5V high level, and 0 corresponds to a 0V low level. Input these waveform files sequentially into arbitrary waveform generator 1. Arbitrary waveform generator 1 outputs the time-coding sequence, controlling microwave switch 3. +1 corresponds to a 5V high level, controlling the conduction of microwave switch 3, and 0 corresponds to a 0V low level, controlling the deactivation of microwave switch 3. The fundamental frequency microwave output from microwave source 2 is modulated by the microwave switch and input to terahertz frequency multiplier 4, generating a terahertz field carrying modulation information. This achieves orthogonal coding modulation with the terahertz field, causing the signal field to interact with the local oscillator field, generating a terahertz differential signal carrying coding information. Input the signal to be measured and interact with the modulated terahertz field to start the measurement sequence. The arbitrary waveform generator sequentially outputs each row of coded waveforms to the microwave switch, while simultaneously sending a synchronous trigger signal to the lock-in amplifier to ensure data accuracy. The interacting terahertz signal is received by atomic gas cell 5, which converts the information into changes in the intensity of the probe laser. Photodetector 6 converts the optical signal into an electrical signal, and a lock-in amplifier demodulates the input electrical signal and stores the data until all measurements of different encoding modes are completed. Measurement vectors are generated by differential and integral preprocessing of the acquired data, and the original information is reconstructed using a reconstruction algorithm.

[0065] The above description is merely an embodiment of the present invention and is quite detailed. However, the scope of protection of the present invention is not limited thereto. For example, cesium atoms can also be alkali metal atoms such as rubidium atoms, and atomic energy levels, laser wavelengths, and terahertz frequencies can use other coupling energy level combinations, etc. Any substitutions or improvements made by those skilled in the art within the scope disclosed in the present invention, based on the technical solution and inventive concept of the present invention, shall fall within the scope of protection of the present invention.

[0066] This invention discloses a broadband atomic terahertz detection method and apparatus. The broadband atomic terahertz detection method includes: generating a time-coded sequence based on an arbitrary waveform generator; controlling a microwave switch to perform orthogonal coding modulation on the terahertz field to generate a terahertz differential signal carrying coded information; the differential signal acts on Rydberg atoms in an atomic gas cell, causing atomic energy level transitions and converting them into optical signals through changes in the intensity of the probe light; the optical signal is converted into an electrical signal by a photodetector, demodulated and acquired by a lock-in amplifier, and then processed by a computer for computational imaging to reconstruct the original time-domain waveform, spectrum, or image information. The broadband atomic terahertz detection apparatus includes a terahertz modulation module, a signal detection module, and a data acquisition and processing module. The terahertz modulation module consists of an arbitrary waveform generator, a microwave source, a microwave switch, and a terahertz transducer; the signal detection module includes an atomic gas cell, a pump and probe laser, and a balanced photodetector; the data acquisition and processing module consists of a lock-in amplifier and a computer. The device of this invention combines superheterodyne detection and time-domain computational imaging algorithms to overcome the limitations of detector bandwidth, expand detector bandwidth, and improve time response speed, thereby achieving fast and highly sensitive terahertz spectrum detection, which can be applied to fields such as materials analysis and encrypted communication.

[0067] Compared with the prior art, the beneficial effects of the present invention include at least the following:

[0068] This invention discloses a broadband atomic terahertz detection method and apparatus. It employs orthogonal coding modulation using a time-coding matrix and effectively separates signal and noise through differential processing. This method effectively suppresses noise and improves the system's signal-to-noise ratio. Rydberg atoms in the atomic gas chamber exhibit extremely high sensitivity to electric fields. This invention fully utilizes this quantum property and combines it with efficient coding modulation to achieve high-sensitivity detection.

[0069] This invention discloses a broadband atomic terahertz detection method and apparatus. It utilizes a microwave switch to perform time-coded modulation of high-frequency terahertz signals, combining time-domain superheterodyne with computational imaging to cleverly circumvent the extreme technical challenges of directly detecting terahertz frequencies. The bandwidth is no longer solely determined by the bandwidth of the photodetector, but rather by the modulation speed, atomic response time, and algorithmic reconstruction capabilities. Through algorithmic "decoding," signals far exceeding the physical bandwidth of the detector itself can be reconstructed.

[0070] This invention discloses a broadband atomic terahertz detection method and apparatus. The inherent compatibility of the time-coding matrix with compressed sensing algorithms enables high-fidelity reconstruction of signals or images from fewer measurements than traditional methods. Furthermore, this invention addresses the challenge of traditional atomic spectroscopy methods, which require slowly scanning laser or terahertz frequencies to acquire the spectrum. By capturing a single time-domain signal and reconstructing it using algorithms, this invention directly obtains the time-domain waveform or transient spectrum, making it possible to observe non-repeatable, rapidly changing terahertz physical phenomena.

[0071] Embodiments of the present invention also provide a broadband atom terahertz detection device for implementing the aforementioned broadband atom terahertz detection method, the device comprising:

[0072] The terahertz modulation module is used to perform orthogonal coding modulation on the terahertz field using a time-coded sequence to generate a terahertz differential signal carrying coded information. It includes:

[0073] An arbitrary waveform generator is used to generate the time-coded sequence;

[0074] A microwave source outputs a fundamental frequency microwave, which is multiplied by a terahertz frequency multiplier to generate a terahertz signal; its output terminal is connected to the signal input terminal of the microwave switch, and after being modulated by the microwave switch, it outputs a terahertz signal carrying modulation information through a terahertz frequency multiplier.

[0075] A microwave switch, the control terminal of which is connected to the output terminal of the arbitrary waveform generator, is driven by the time-coded sequence;

[0076] A terahertz frequency multiplier multiplies the fundamental frequency microwave output from a microwave source to obtain a terahertz signal.

[0077] A signal detection module, used to convert the information carried by the terahertz differential signal into an electrical signal, includes:

[0078] A pump laser and a probe laser are used to emit a coupling laser and a probe laser, respectively. The frequencies of the probe laser and the coupling laser are locked and then collinearly irradiate the atomic gas cell to prepare atoms to the Rydberg state.

[0079] The atomic gas chamber is filled with alkali metal atomic vapor. Its main function is to convert the received terahertz differential signal into the transmitted light intensity signal of the probe light.

[0080] A photodetector is disposed in the transmission optical path of the detection laser to receive changes in the intensity of the transmitted light and convert them into electrical signals.

[0081] It should be noted that this device is a device corresponding to the above method. All implementation methods in the above method embodiments are applicable to this embodiment and can achieve the same technical effect.

[0082] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A broadband atomic terahertz detection method, characterized in that, The method includes: Step 101: Use an arbitrary waveform generator to generate a time-coded sequence, control a microwave switch to perform orthogonal coding modulation on the terahertz field, and generate a terahertz differential signal carrying coded information by the interaction between the terahertz signal field and the local oscillator field. Step 102: Apply the terahertz differential signal to the Rydberg atoms in the atomic gas cell to convert the terahertz information into changes in the transmitted light intensity of the probe light, and convert the optical signal into an electrical signal. Step 103: Synchronously demodulate and acquire the electrical signal to generate a measurement vector, and reconstruct the original terahertz time-domain waveform from the measurement vector using a compressed sensing reconstruction algorithm; generate a terahertz differential signal carrying coded information, specifically including: The generated specific time encoding matrix is ​​input into the arbitrary waveform generator, and the time encoding matrix has orthogonality and binaryity; The microwave switch is driven by the arbitrary waveform generator to perform orthogonal coding modulation on the terahertz signal according to the coding sequence of each row of the time coding matrix, so as to generate the terahertz differential signal.

2. The broadband atomic terahertz detection method according to claim 1, characterized in that, Converting terahertz information into changes in the transmitted light intensity of the probe light specifically includes: Alkali metal atoms were prepared to the Rydberg state by irradiating an atomic gas cell in a collinear manner with a probe laser and a coupling laser. By locking the frequencies of the probe laser and the coupling laser to specific atomic energy level transitions, an electromagnetically induced transparency effect is formed in the atomic gas cell, and the EIT transmission peak of the probe light is obtained. The terahertz differential signal carrying the encoded information interacts with the atoms in the Rydberg state. The energy of the terahertz photon resonates with the atomic energy level and causes the atomic energy level to transition. The EIT transmission peak is modulated by the change of quantum state, thereby converting the terahertz information into the change of the transmitted light intensity of the probe light. A balanced photodetector is used to receive the probe laser carrying terahertz information emitted from the atomic gas chamber and convert the optical signal into an electrical signal.

3. The broadband atomic terahertz detection method according to claim 2, characterized in that, The electrical signal is synchronously demodulated and acquired to reconstruct the original terahertz time-domain waveform, specifically including: The electrical signal is demodulated and acquired using a lock-in amplifier, and the signal is preprocessed by differential and integral operations using computer code to generate a measurement vector. The compressed sensing reconstruction algorithm is used to process the measurement vector to reconstruct the original terahertz time-domain signal with high fidelity using fewer measurements than the Nyquist sampling rate. A noise reduction algorithm is used to optimize the reconstructed time-domain signal.

4. The broadband atomic terahertz detection method according to claim 3, characterized in that, In the process of generating terahertz differential signals and data demodulation and acquisition after encoding and modulating terahertz waves, an external signal source is used to externally synchronize the arbitrary waveform generator and lock-in amplifier to maintain hardware synchronization. The lock-in amplifier synchronously integrates the demodulated signal within a fixed integration time window for each line of time encoding to obtain the corresponding measurement value.

5. A broadband atomic terahertz detection device, used to implement the broadband atomic terahertz detection method as described in any one of claims 1-4, characterized in that, The device includes: The terahertz modulation module is used to perform orthogonal coding modulation on the terahertz field using a time-coded sequence to generate a terahertz differential signal carrying coded information. It includes: An arbitrary waveform generator is used to generate the time-coded sequence; A microwave source outputs a fundamental frequency microwave, which is multiplied by a terahertz frequency multiplier to generate a terahertz signal; its output terminal is connected to the signal input terminal of the microwave switch, and after being modulated by the microwave switch, it outputs a terahertz signal carrying modulation information through a terahertz frequency multiplier. A microwave switch, the control terminal of which is connected to the output terminal of the arbitrary waveform generator, is driven by the time-coded sequence; A terahertz frequency multiplier multiplies the fundamental frequency microwave output from a microwave source to obtain a terahertz signal. A signal detection module, used to convert the information carried by the terahertz differential signal into an electrical signal, includes: A pump laser and a probe laser are used to emit a coupling laser and a probe laser, respectively. The frequencies of the probe laser and the coupling laser are locked and then collinearly irradiate the atomic gas cell to prepare atoms to the Rydberg state. The atomic gas chamber is filled with alkali metal atomic vapor. Its main function is to convert the received terahertz differential signal into the transmitted light intensity signal of the probe light. A photodetector is disposed in the transmission optical path of the detection laser to receive changes in the intensity of the transmitted light and convert them into electrical signals.

6. A computing device, characterized in that, include: One or more processors; A storage device for storing one or more programs that, when executed by one or more processors, cause the one or more processors to implement the method as described in any one of claims 1 to 4.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a program that, when executed by a processor, implements the method as described in any one of claims 1 to 4.

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