We describe a He3-Xe129 comagnetometer using Rb87 atoms for noble-gas spin polarization and detection. We use a train of Rb87 π pulses and σ+/σ-optical pumping to realize a finite-field Rb magnetometer with suppression of spin-exchange relaxation. We suppress frequency shifts from polarized Rb by measuring the He3 and Xe129 spin precession frequencies in the dark, while applying π pulses along two directions to depolarize Rb atoms. The plane of the π pulses is rotated to suppress the Bloch-Siegert shifts for the nuclear spins. We measure the ratio of He3 to Xe129 spin precession frequencies with sufficient absolute accuracy to resolve Earth's rotation without changing the orientation of the comagnetometer. A frequency resolution of 7 nHz is achieved after integration for 8 h without evidence of significant drift.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)