5 results about "Helium atom" patented technology

A traceable multi-mode extremely weak magnetic field measuring device and method, comprising helium-3 atoms and an atomic magnetometer in a spin-exchange relaxation-free state, the helium-3 atoms polarized by metastable exchange optical pumping under an extremely weak magnetic field provide a traceable magnetic field value for the atomic magnetometer, the value is compared with the output response of the atomic magnetometer to obtain a calibrated scale factor of the atomic magnetometer, so that the measurement values of the atomic magnetometer are traceable. The atomic magnetometer meter head comprises four independent detection channels, the four detection channels are obtained by beam splitting of two detection lasers with different frequency detuning amounts, and the channels have high consistency. The method proposed by the application is compatible with the cooperative use of multiple probes, and can realize single-meter-head multi-channel measurement, meter-head internal magnetic field gradient measurement and meter-head inter-magnetic field gradient measurement three measurement modes, each mode has high consistency and high sensitivity.

The invention discloses a geomagnetic field accurate measurement method and device based on optical detection helium-3, and the method comprises the steps: achieving nuclear spin polarization through optical pumping and metastable state spin exchange, applying a pulse magnetic field to excite a helium-3 nuclear spin FID signal, and detecting the frequency and relaxation rate of the helium-3 nuclear spin FID signal; a theoretical model is constructed, parameters such as helium 3 atomic number density and relaxation rate in a gas chamber are measured in combination with spin exchange frequency shift and a relaxation phenomenon, a conversion formula of FID frequency and helium 3 ground state Larmor frequency is established based on the parameters, and frequency shift caused by spin exchange is corrected; the residual magnetism of the probe is inversed through multi-angle measurement, errors introduced by the residual magnetism are eliminated, and finally accurate measurement of the geomagnetic field is achieved. The invention provides a geomagnetic field accurate measurement method and device based on optical detection helium-3, which are used for carrying out complete system error correction and elimination aiming at spin exchange and probe residual magnetism system errors in an optical detection type geomagnetic field helium-3 magnetometer, and can solve the problem that the accuracy and the sensitivity of geomagnetic field measurement are difficult to consider at the same time.

The invention relates to the technical field of atom magnetometer detection and quantum sensing, and discloses a helium atom metastable state excitation density detection method, which comprises the following steps: constructing a detection system comprising a distributed feedback laser, a helium atom gas chamber, an excitation circuit and an oscilloscope; respectively acquiring an unexcited state transmission light signal, an excited state transmission light signal and a background signal by using an oscilloscope; spontaneous radiation interference is eliminated through background subtraction, laser power fluctuation is eliminated through normalization, and the helium atom metastable state excitation density is obtained through inversion according to the Lambert-Beer law. According to the invention, the helium atom metastable state excitation density inverted in real time is used as a feedback basis, and the density change is monitored to lock the optimal resonance point and impedance matching parameters of the excitation circuit. According to the invention, the influence of plasma discharge interference and laser power fluctuation is effectively eliminated, the measurement signal-to-noise ratio and accuracy are improved, and the preparation efficiency of metastable helium atoms is maximized.

The invention provides a helium atom gas chamber capacitance test method, and relates to the technical field of magnetic field measurement, and the method comprises the following steps: analyzing the capacitance change condition of a helium atom gas chamber before and after radio frequency excitation, and laying a foundation for the precise measurement of capacitance parameters through a targeted scheme; aiming at the capacitance change condition before radio frequency excitation of the helium atom gas chamber, a network analyzer is adopted to realize precise measurement of the capacitance of the helium atom gas chamber after radio frequency excitation by measuring radio frequency reflection parameters; aiming at the capacitance change condition after radio-frequency excitation of the helium atom gas chamber, the optimal excitation radio-frequency frequency is determined by adopting a signal source matching excitation and quantum magnetic measurement system comprehensive analysis mode, so that accurate measurement of the capacitance of the helium atom gas chamber after radio-frequency excitation is realized.

The invention provides a high-temperature temperature measurement method, device and equipment based on a tungsten-based material. The invention relates to the technical field of high temperature measurement, and the method comprises the steps: obtaining the surface morphology of a tungsten-based temperature measurement sample before measurement, placing the tungsten-based temperature measurement sample in an environment to be subjected to temperature measurement, and carrying out the temperature measurement for a preset time; acquiring a surface topography image of the tungsten-based temperature measurement sample after helium irradiation based on an electron microscope, and determining target statistical characteristics of a preset observation point in combination with the surface topography before measurement; on the basis of diffusion activation energy of a diffusion mechanism of helium atoms in tungsten crystals, determining an incidence relation between the temperature and a target diffusion coefficient by combining a Boltzmann constant; determining helium bubble size information on the surface of the tungsten-based temperature measurement sample based on the target statistical characteristics, and calculating a thermal history corresponding to the environment to be subjected to temperature measurement in combination with the helium bubble size information and the association relationship; and calculating the temperature of the environment to be subjected to temperature measurement in combination with the thermal history corresponding to each preset observation point. According to the method provided by the invention, high-precision temperature measurement can be realized in an extreme environment.