Quadrupolar interaction induced frequency shift of 131Xe nuclear spins on the surface of silicon

Abstract

The combination of micro-machined technology with atomic spin gyroscope (ASG) devices can be used to fabricate a chip-scale atomic spin gyroscope (CASG). The core of the gyroscope is a micromachined vapour cell, which contains alkali metal and isotope-enriched noble gases, such as $^{129}Xe$ and $^{131}Xe$. The quadrupolar frequency shift of $^{131}Xe$ is a key parameter that can affect the drift of the ASG and is related to the material of the cell in which they are contained. In micromachining technology, the utilised material is silicon. In this study, we investigated the electric quadrupolar frequency shift of $^{131}Xe$ atoms with the silicon wall of a micro-machined vapour cell. A cylindrical micromachined vapour cell was utilised in the experiment, and a large part of the inner cell surface comprised silicon material. We studied the temperature dependence of the $^{129}Xe$ spin relaxation and $^{131}Xe$ frequency shifts to evaluate the interaction of the nuclear spin with the container wall and alkali metal atoms. The results show that the average twisted angle of the $^{131}Xe$ nuclear spins as they collided with the silicon wall was measured as $29 \times 10^{-6} rad$. The desorption energy required for the $^{131}Xe$ nuclear spin to escape from the silicon surface was $E_{si}=0.009 eV$. This study could help improve the bias stability of the CASG, which is a key parameter for the gyroscope, and may help to develop a method to study the surface properties of various materials.

In Situ Study of the Magnetic Field Gradient Produced by a Miniature Bi-Planar Coil for Chip-Scale Atomic Devices

“…The FID signal is caused by the precession of the 131 Xe nuclear spins around the holding magnetic field. We fitted the signal to a sinusoidal function multiplied by an exponential decay function [41,42], and we calculated the precession frequency and the decay rate of the FID signal to be 1.4 Hz and 0.50 s −1 , respectively. According to the gyro-magnetic ratio of 131 Xe, which is 0.0042 Hz/nT, the total magnetic field can be calculated to be 381 nT.…”

Theoretical Study of Measuring Moving MEGs with 83Kr Based Atomic Co-Magnetometer

“…129 Xe, 131 Xe could also be used. However, due to the large collision relaxation with the container walls, it is hard to polarize the nuclear spins [30][31][32]. For 83 Kr nuclear spins whose atom mass is much smaller than that of the Xe atoms, we could estimate a smaller wall relaxation as well as a weaker interaction strength between the alkali atoms.…”