A5078865867- Atomic and Subatomic Physics Research
- Cold Atom Physics and Bose-Einstein Condensates
- Quantum optics and atomic interactions
- Advanced MRI Techniques and Applications
- Dark Matter and Cosmic Phenomena
- Mechanical and Optical Resonators
- Geophysics and Sensor Technology
- Quantum, superfluid, helium dynamics
- Functional Brain Connectivity Studies
- NMR spectroscopy and applications
- Magnetic Field Sensors Techniques
Peking University
2017-2023
Beijing Meteorological Bureau
2023
ORCID
2021
High-sensitivity total-field atomic magnetometer enables brain-activity measurements in unshielded Earth’s field.
Abstract Ultralight bosons such as axion-like particles are viable candidates for dark matter. They can form stable, macroscopic field configurations in the of topological defects that could concentrate matter density into many distinct, compact spatial regions small compared with Galaxy but much larger than Earth. Here we report results search transient signals from domain walls by using global network optical magnetometers exotic (GNOME) physics searches. We data, consisting correlated...
A magnetically-quiet environment is important for detecting faint magnetic-field signals or nonmagnetic spin-dependent interactions. Passive magnetic shielding using layers of large magnetic-permeability materials widely used to reduce the noise. The noise can also be actively monitored with magnetometers and then compensated, acting as a complementary method passive shielding. We present here general model quantitatively depict optimize performance active stabilization experimentally verify...
Abstract Numerous observations suggest that there exist undiscovered beyond‐the‐standard‐model particles and fields. Because of their unknown nature, these exotic fields could interact with standard model in many different ways assume a variety possible configurations. Here, an overview the global network optical magnetometers for physics searches (GNOME), ongoing experimental program designed to test wide range scenarios, is presented. The GNOME experiment utilizes worldwide shielded atomic...
In this article, the dependence of frequency response a close-loop Bell-Bloom magnetometer on its various experimental parameters is studied. With proper setting feedback parameters, bandwidth, limited by low pass filter bandwidth in Lock-in amplifier, can be extended far beyond open-loop bandwidth. The data show good agreement with simulation results.
Abstract Results are reported from the first full-scale search for transient signals exotic fields of astrophysical origin using data a newly constructed Earth-scale detector: Global Network Optical Magnetometers Exotic physics searches (GNOME). Data collected by GNOME consist correlated measurements optical atomic magnetometers located in laboratories all over world. searched patterns propagating through network consistent with composed ultralight bosons such as axion-like particles (ALPs)....
In this article, the dependence of magnetic resonance signal amplitude on frequency detuning probe light in Faraday-rotation alkali atomic magnetometers is quantitatively studied. The sensitivity can be improved by proper because larger Signal-to-Noise ratio (SNR).
We investigate vapor cells with antirelaxation wall coatings by measuring their relaxation properties beyond the melting temperatures and compare behavior of coating material as observed differential scanning calorimetry.
In this article, we study how variables induced by the vapor cell, such as magnetic resonance width and amplitude, affect frequency response of a closed-loop magnetometer. For cells with different characteristics, responses for same PID parameters are different. The experimental data coincides well theoretical calculation.
In this work, a scalar Cs magnetometer based on amplitude modulated nonlinear magneto-optical rotation (AM NMOR) is demonstrated and has reached 0.23 pT/√{Hz} at 1 Hz from 10000 nT to 60000 nT. Besides, potassium experimentally built with totally separated magnetic resonance signals in larger geomagnetic field, where the performance of limited by Zeeman effect.
Many terrestrial experiments have been designed to detect domain walls composed of axions or axionlike particles (ALPs), which are promising candidates dark matter. When the wall crosses over Earth, pseudoscalar field ALPs could couple atomic spins. Such exotic spin-dependent couplings can be searched for by monitoring transient-in-time change spin precession frequency in presence a magnetic field. We propose here single-species cesium comagnetometer, measures frequencies atoms different...
We use an optical method instead of the circuit's to shift phase and realize all-optical self-oscillating <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sup> He atomic magnetometer, in which bandwidth is more than 1kHz sensitivity 2pT/Hz1/2 @10 Hz-500 Hz. This magnetometer suitable for magnetic field stabilization by real-time feedback changes through a voltage-controlled constant current source connected field-stabilized coils, provides...
We present theoretical study of the Hanle effect in metastable state <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sup> He atoms with arbitrarily polarized light. The orientation and alignment components atomic polarization produce resonance signals different line shapes. amplitudes shapes have significant dependence on light polarization. Our results can be used as an efficient method to determine component laser light, which is crucial...
In this article, we present a novel method to measure the residual magnetic field in shield. Because of nonlinear Zeeman effect, resonance width will grow with increasing field. By detecting dependence signal on applied field, shield can be deduced. The error deduced value and true less than 1.5 nT. Higher sampling rate result error.