Raman subrecoil spectroscopy of cold cesium atoms

We describe and characterize a setup for subrecoil stimulated Raman spectroscopy of cold cesium atoms. We study in particular the performances of a method designed to active control and stabilization of the magnetic fields across a cold-atom cloud inside a small vacuum cell. The performance of the setup is monitored by {\em copropagative-beam} stimulated Raman spectroscopy of a cold cesium sample. The root mean-square value of the residual magnetic field is 300 $\mu G$, with a compensation bandwidth of 500 Hz. The shape of the observed spectra is theoretically interpreted and compares very well to numerically generated spectra.