Figure 1: Microfabricated ¹²⁹Xe polarizer.

(a) A mixture of Xe and N₂ gas flows from an external gas manifold into the chip. Circularly polarized 795 nm laser light optically pumps a hot Rb vapor in the pump chamber. As ¹²⁹Xe flows through the pump chamber, it is polarized by spin exchange interactions with the optically pumped Rb. Additional 795 nm laser beams are used to optically probe the magnetic field in the pump and probe chambers, while causing minimal perturbation to the polarization state; the beams enter the chambers at 45° from normal to the chip surface. (b) The silicon chip has lateral dimensions of 39 mm × 19 mm, with a thickness of 1 mm. The pump and probe chambers both have lateral dimensions of 4 mm × 4 mm. The microchannel connecting the pump and probe chambers is 10 mm long × 1 mm wide. Two tall grooves are etched from the middle of the chip to thermally isolate the two sides of the device. The outside chambers act as attachment sites for glass connections to an external vacuum and gas handling system and have lateral dimensions of 5 mm × 10 mm.