An atomic magnetometer with no response blind zone and its method for measuring external magnetic field

Abstract

The present invention provides an atom magnetometer without a response blind area. The atom magnetometer comprises a laser, an expanded beam collimation device, a circularly polarized light conversiondevice, an acoustic optical modulator, an Helmholtz coil, an atom air chamber, a reflector set, a photoelectric detector, a lock-in amplifier, a signal processing system and a heating device. The atom magnetometer is simple in structure; and two exciting methods which apply an excitation magnetic field and perform light modulation are combined, and components of the total spin angular momentum ofa sensing atom in two directions are detected to achieve measurement of a blind area without response. The present invention further discloses a method for measuring an external magnetic field by employing an atom magnetometer without response blind area and method. The measurement method is simple, has no response blind area, can rapidly and accurately obtain related data of an external magneticfield, and is high in practicability.

Description

technical field [0001] The invention relates to the technical field of weak magnetic field detection, in particular to an atomic magnetometer with no response blind zone and a method for measuring an external magnetic field. Background technique [0002] In many vital fields, such as basic physics research, biomedicine, deep space exploration, geological exploration, earthquake prediction, and nuclear magnetic resonance signal detection, there is an urgent need for effective detection of weak magnetic fields. At present, the common magnetometers mainly include fluxgates, Hall devices, proton magnetometers, superconducting quantum interference devices and atomic magnetometers. Among them, the superconducting quantum interference device is the most sensitive magnetometer put into application at present, and it has realized magnitude of sensitivity. However, superconducting quantum interference devices are inconvenient to use due to the need for huge refrigeration equipment,...

AI Technical Summary

Problems solved by technology

When the external magnetic field is parallel to the probe light, since the component of the total spin angular momentum of the sensing atoms along the direction of light propagation will not precess around the external magnetic field, the effective detection of the external magnetic field cannot be realized.

[0005] It can be seen from the above that when the external magnetic field is along certain directions, some common atomic magnetometers will not be able to effectively detect the external magnetic field, that is, there is a response blind zone

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