On EIT line shape in a standing-wave pump field and parametric analysis

A study to understand the electromagnetically induced transparency (EIT) in a standing wave pump field has been reported in this paper. We have solved analytically the density matrix equation for a Λ-type system in the presence of the standing wave pump field, and a closed form expression of the standing wave EIT (SW-EIT) is obtained. The usual traveling wave EIT (TW-EIT) is split in the presence of the standing wave pump field with an EIA like structure at the center of the probe absorption profile. The EIA structure at the center is enhanced with the increase in the vapor cell length. Multiple splitting of the standing wave EIT is observed, when the pump power is varied for a wide range. The localization of the atom in the standing wave field has also been studied, and it has been observed that the order of localization is dependent on the detuning of pump and probe field and also on the pump Rabi frequency.