Precise Raman control of spinor matterwave with nanosecond composite biased rotations

We experimentally demonstrate precise Raman matterwave control at an intermediate single-photon detuning where a balance between the optical power efficiency with the requirements on the control speed and the suppression of excited-state dynamics can be adjusted. The method is based on composite biased rotation that exploits the proportionality between the traditionally “unwanted” light shift with the Raman coupling. The nanosecond control is fast enough to be immune to low-frequency noises, so our system can be accurately modeled. The ℱ> 99.2% fidelity is estimated with standard single-qubit quantum process tomography and randomized benchmarking methods. Our work suggests highly precise spinor matterwave controls are achievable for large atomic samples with moderate laser power, even in noisy environment.