The Influence Of A Kerr Medium On The Resonance Fluorescence Spectrum Of Two-level Atoms In A Cavity

Atomic resonance fluorescence characteristics is an important issue concerning the interaction between the atom and the light field. This paper studies the influence of the Kerr medium on the Fluorescence spectrum of two-level atomic ensemble in a cavity field. Starting from the Hamiltonian, we can derive the Langevin equations, and then we calculate the steady-state solutions, diffusion coefficients and the linear Langevin equations. Finally we plot the figure of atomic fluorescence spectrum. We mainly consider the changing of the atomic fluorescence spectrum after we add the Kerr medium. We also consider the other cases by changing the cavity field attenuation, the atomic detuning, the driving field rabi frequency,and the cooperative parameters. The results are presented as follows.1. Due to the interaction between the atomic ensemble and the cavity field,We find there nine peaks structure in the atomic fluorescence spectrum, i.e. each ancient peak in the abscence of the cavity field’s interaction splits into three peaks. Note that the middle peak exhibit a very narrow spectral lines.2. By adding the Kerr medium, a ultra-narrow peak arises at the zero frequency of the atomic fluorescence spectroscopy. When the Kerr coefficient is less than a certain value, the height of ultra-narrow peak increases with the increase of Kerr coefficients. When the Kerr coefficient is more than the certain value, the height of ultra-narrow peak decreases with the increase of Kerr coefficients.3. The sidebands value of the atomic fluorescence spectrum deeply depend on the value of the cavity field attenuation, the atomic detuning, the driving field rabi frequency. When the cavity field attenuation increases, the value of two sidebands increases along with the decay rate increases, and the value of zero frequency peak change keeps almost the same. As the atomic detuning increases, the value of center peak, which splits from the two sidebands, the value of two sidebands increases to the maximum value and then decrease afterwards. As the driving field rabi frequency increases, the value of two sidebands change along with the driving field rabi frequen-cy, The position of two sidebands depend on the value of two times of driving field rabi frequency.