Laser amplification without population inversion on the D-1 line of the Csatom with semiconductor diode lasers

The importance of lasing without inversion (LWI) in comparison with the use of nonlinear optical techniques and techniques based on high-intensity fem tosecond light pulses to generate high-frequency coherent radiation is outl ined, The original development and utilization of an experimental facility based on semiconductor diode lasers to study the fundamental aspects of LWI on the D-1 line of the Cs atom, which is rarely attempted, is described. T his experimental facility is used to observe inversionless amplification on the D-1 line of the Cs atom by use of a A atomic scheme, A combination of EIT and broadband pumping of atoms from the lower to the upper level of the probe transition allowed the observation of the inversionless gain. Justif ication for the absence of inversion in the probe transition is provided. W e report a single-pass inversionless gain of approximate to 11% with relati vely weak incoherent pumping. The results show improvement over the previou sly reported inversionless gain observed in Na, Rb, and Cs, illustrating th e potential advantage of using the D-1 line of Cs. (C) 2001 Optical Society of America.