Predictive thermal model for indirect temperature measurement inside atomic cell of nuclear magnetic resonance gyroscope

Abstract

This paper describes a methodology for predicting temperatures inside a micro-device at critical locations where thermal sensors cannot be placed. The device under study is a nuclear magnetic resonance gyroscope, an instrument that is highly sensitive to temperature variations. A physical thermal model of the device is developed and validated using experimental measurements from a prototype. A compact thermal model which approximates the behavior of the physical system is obtained through a sequential selection algorithm (with RMS error of approximately 0.15ºC). The compact thermal model can be solved rapidly and is therefore suitable for real-time feedback control of the temperature inside the atomic cell.

Measuring the spin polarization of alkali-metal atoms using nuclear magnetic resonance frequency shifts of noble gases

“…The temperature sensitivity of an NMR gyroscope is theoretically estimated to be on the order of 1 deg/h/mK. 24,25 Therefore the temperature stability of…”

Nuclear magnetic resonance gyroscopes

“…Like the micro glassblown cells, these cells also allow for pumping and probing along different directions. Shkel's group has also performed work on thermal modeling related to NMRGs [68]. A summary of the components developed in Shkel's group as well as their integration can be found in [69].…”

In-situ measurement and close-loop control of atomic number density in an optically pumped magnetometer based on light absorption

“…Jimenez-Martinez et al used the optical depth to detect the atomic number density of Cs in an Mx magnetometer and a Bell-Bloom magnetometer [29]. Salleras et al used transmitted light intensity to measure the temperature of the vapor cell in nuclear magnetic gyroscopes [30]. These light absorption methods have been successfully used for the measurement of the atomic number density.…”