Optimization and control of cold atom interference phase shiftbased on laser double-sideband suppression br

Using the electro-optical modulation method to generate Raman beams for cold atom interference is one ofthe better methods for constructing a more compact and robust laser system. But this way will generate someresidual sidebands resulting in the additional interference phase shift, which can affect the measurementaccuracy of cold atom interferometer. In order to weaken the effect of laser modulation sidebands on the phaseshift of cold atom interference, a double-sideband suppressed-carrier modulation laser system for cold atominterference is constructed. Based on the designed laser system, the principle of double-sideband generation andsuppression is analyzed in detail, and some residual sidebands are adjusted and controlled. Moreover, someimportant optical parameters that affect the phase shift of cold atomic interference, such as the initial distancebetween the Raman retro-reflection mirror and the atomic cloud, the interrogation time between two adjacentRaman pulses, the laser modulation depth and the initial velocity of the atomic cloud, are discussed andoptimized. By optimizing these relevant parameters, the influence of residual modulation sidebands on the phaseshift of cold atomic interference is weakened drastically. The research results indicate, making use of the methodof double-sideband suppression, the phase shift of cold atomic interference can be optimized to 0.7 mrad whenthe initial distance between the Raman retro-reflection mirror and the atomic cloud is 105 mm, and theinterrogation time between two adjacent Raman pulses is 82 ms. More importantly, this work can provide amethod for weakening the influence of Raman sideband effect on the phase shift of cold atom interferometer,and the corresponding laser system can be applied to other inertial sensors such as atomic gravimeter or atomicgravity gradiometer