Tungsten Thermionic Emission as a Gauge for Low Pressures of Cesium Vapor

Heated metal filaments under electric fields and low pressures of alkali metal gas eject electrons by thermionic emission as a function of the pressure of the gas and the temperature of the filament. To explore this process in a program to develop large-area alkali metal photocathodes, we have designed and built a gauge following the studies of Taylor and Langmuir. We present proof-of-principle measurements of the thermionic emission of a tungsten filament in cesium vapor. We describe a second-generation design that corrects flaws in the first gauge.

Effect of the magnetically induced dichroism on the distribution of atomic polarization in Cesium vapor cells

Distribution of the atomic polarization in a Cesium vapor cell, induced by optical pumping, is analytically calculated and discussed when an external magnetic field interacts with the system. Based on the rate equations of the optically pumped atomic system and considering the effect of magnetically induced dichroism on the absorption of polarized propagating light, we have obtained the light intensity and atomic polarization distribution along the propagation direction of the gas cell. It is shown that based on the initial light polarization and the laser detuning, the external magnetic field considerably changes the polarization distribution. The obtained results of the polarization distribution versus applied magnetic field can be used for different investigations, including the study of the atomic magnetometer’s sensitivity.