Control of coherence in a ladder type system with double resonance optical pumping and electromagnetically induced transparency

Revisiting the four-level inverted-Y system under both Doppler-free and Doppler-broadened conditions: an analytical approach

“…This assumption is purely for the purpose of calculation. The actual energy level structure of 87 Rb allows one part of the population that is pumped to the D 5 5 2 level to decay to the closely spaced 6P energy levels and finally fall back to the 5S state by emitting a fluorescence signal of 420.2 nm [6,32,33]. The remaining part of the population of the 5D 5 2 state decays spontaneously to the P 5 3 2 state with a spontaneous decay rate of 0.97 MHz [33].…”

“…The actual energy level structure of 87 Rb allows one part of the population that is pumped to the D 5 5 2 level to decay to the closely spaced 6P energy levels and finally fall back to the 5S state by emitting a fluorescence signal of 420.2 nm [6,32,33]. The remaining part of the population of the 5D 5 2 state decays spontaneously to the P 5 3 2 state with a spontaneous decay rate of 0.97 MHz [33]. We have not considered any additional decay path for the population of the uppermost level ñ 3 | in this article, rather spontaneous decay of population from this level to the state ñ 2 | has only been considered (refer to figure 1).…”

Multi-level cascaded electromagnetically induced transparency in cold atoms using an optical nanofibre interface

“…Due to the presence of the cooling and the repump beams coupling to the two ground states, (5 S 1/2 F=2 and 5 S 1/2 F=1), the population of these two states should be constant. Reduction of the DROP effect due to the presence of the repump beam has been studied for Rb vapour recently [31]. The width of the EIT signal is dependent on the coherence properties of atoms in the system.…”