OPTICAL-PUMPING OF RB VAPOR USING HIGH-POWER GA1-XALXAS DIODE-LASER ARRAYS

The use of high-power Ga1-xAlxAs diode laser arrays for optical pumping of Rb vapor has been examined both theoretically and experimentally. Our studies show that large atomic polarizations can be obtained using the broad spectral output of a diode laser array if the Rb resonance line is collisionally broadened by several atmospheres of a buffer gas. The objective was to study the effectiveness of diode laser arrays as light sources for optically pumped spin-exchange polarized He3 targets. The average Rb polarization was deduced at three different Rb vapor pressures using the polarization induced in the He3 buffer gas. The largest He3 polarization observed was 53% using a 20-W diode array with 1.9-nm full width at half maximum spectral width in 10.5 amagat of He3. This result compares favorably with other light sources for this target. The measured average Rb polarizations are compared to theoretical calculations. © 1995 The American Physical Society.