Self-induced transparency effect

Mode-locking in a laser with a coherent absorber

“…We believe that the mode locking effect in this case is possible only in the regime of coherent interaction of light with matter. This regime is significantly different from the bleach ing of the medium in the case of the usual saturation of absorption, which occurs at τ p > T 2 (see reviews [17,18]), when the capability of the medium to absorb or emit energy is proportional to the difference between the populations of the upper and lower levels. Such a pulse cannot transfer the medium to an inverted state and its interaction with the medium leads to the equal ization of the populations of the upper and lower lev els.…”

“…A new type of mode locking was considered in recent theoretical works analyzing the possibility of the appearance of stable pulse trains in lasers owing to the coherent character of the interaction of light with the medium of the absorber [8,9], as well as of both the amplifier and absorber [10][11][12][13][14][15]. We note that the features of the coherent interaction of light with absorbing and amplifying media have been known for a long time (see, e.g., [16][17][18][19]). In theoretical works [10][11][12][13][14][15], it was shown that the coherent mode locking regime occurs because of the formation of a 2π pulse of self induced transparency in the absorbing medium and π pulse in the amplifying medium, when the media of the amplifier and absorber are mixed in volume.…”

Ultrashort pulses in an inhomogeneously broadened two-level medium: soliton formation and inelastic collisions

“…It is known that the area theorem (1) is strictly valid only for the inhomogeneously broadened media, though the main features of SIT can be observed in the case of homogeneous broadening as well [6]. This was confirmed recently by Yu et al [26] who performed the direct simulations of area change.…”

Disordered resonant media: Self-induced transparency versus light localization

“…The SIT effect was experimentally observed in a number of systems [17], both gaseous (vapors of alkali metals and rare-earth-metal ions, molecular gases) and solid (semiconductors, doped crystals). As specific and more recent examples, we mention SIT in erbium-doped fibers [32] and quantum-dot waveguides [33], which well correspond to our one-dimensional problem.…”

“…Therefore, it seems to be of great interest to investigate optical response of the disordered media when the light frequency is close to the frequency of atomic resonance. This proximity to the resonance results in a bunch of nonlinear optical effects such as self-induced transparency (SIT) [16,17], optical bistability [18,19], optical kinks [20,21], unipolar pulse generation [22], population density gratings formation [23,24], etc. However, resonant nonlinearities are rarely considered in the literature on disordered photonics.…”