Multiphoton hyperfine Raman transitions with different quantization axes

The quantization axis defines the local interaction between the electromagnetic fields and the atoms. We studied both theoretically and experimentally the hyperfine Raman transition with different quantization axis and found a four-photon Raman transition which happened when the quantization axis is shifting from being parallel to perpendicular to the Raman beams' direction. It keeps the magnetic-field-insensitive feature like the two-photon Raman transition but can be used straightforwardly in multidimensional applications, like inertial sensors or even higher-dimensional quantum walk systems. In addition to inertial sensors, we also discuss the potential quantum sensing applications in magnetometers when the quantization axis is away from perpendicular due to magnetic-field perturbations.