Experimental setup to fabricate Rb–Xe gas cells for atom spin gyroscopes

Abstract

An experimental setup to fabricate atomic vapor cells for atom spin gyroscope application, containing 87Rb, 129Xe, 131Xe, N2, and H2, is described. The setup comprises a high-vacuum chamber, an 87Rb ampule, a glass cell, gas lines, and a turbopump. First, the glass cell is baked for a week at 450 °C to reduce outgassing from the inner walls of the glass cell. Next, rubidium atoms are evaporated into the cubic glass cell. Then, the cubic glass cell is cooled to 2 °C to increase the amount of 87Rb in the cubic glass cell while the vacuum chamber is heated to 100 °C. 6 Torr of 129Xe, 48 Torr of 131Xe, 140 Torr of N2, and 24 Torr of H2 are injected into the cubic glass cell. The sealing method employs pinch-off glass welding. The transverse spin relaxation times of 129Xe and 131Xe at a magnetic field of 6.2 µT applied to the quantization axis are measured to be 8.1 and 16.5 s, respectively, at a cell temperature of 96 °C using nuclear magnetic resonance spectroscopy. The pressure ratio between 129Xe and 131Xe is determined by comparing the output signals from our atom spin gyroscope. The signal-to-noise ratios are 2500 for 129Xe and 3333 for 131Xe, respectively, and the expected angular random walk of the atom spin gyroscope is 0.062°/h1/2 with a 1-Hz repetition rate.