Absorptionless self-phase-modulation via dark-state electromagnetically induced transparency

Optical Vortex Cat States and their Utility for Creating Macroscopic Superpositions of Persistent Flows

“…On the other hand, EIT-enhanced Kerr effects raise the possibility of creating the cat states using shorter PCF lengths, thereby potentially reducing the detrimental effects of dissipation. Furthermore, there are proposals for realizing SPM in atomic vapors with no associated linear medium absorption utilizing two-level EIT and dark states [48], though the linear absorption of the fiber glass would remain. However, since the atomic vapor would supply an optical nonlinearity orders of magnitude larger than the fiber glass the fiber lengths needed would be greatly reduced with respect to conventional fibers.…”

Electromagnetically induced transparency and enhanced self-Kerr nonlinearity in a four-level scheme

“…The large enhancement of nonlinear susceptibilities in EIT-related media leads to the study of nonlinear optics at low light levels because it is responsible for efficient nonlinear optical processes such as frequency conversion [17][18][19], the generation of optical solitons [20], polarization phase gates [21], and so on. With a combination of dark states and two-level EIT, Wong et al [22] showed that a large Kerr nonlinearity can be produced without pump or probe absorption. In addition, spontaneous emission is eliminated because there is no population in the excited state.…”

Enhanced index and negative dispersion without absorption in driven cascade media

“…Manson et al [25] observed the nonlinear response of absorption and dispersion of a driven nuclear-magnetic-resonance two-level system in diamond. With a combination of two-level EIT and dark states [26], large self-phase modulation can be produced without probe absorption [27]. Moreover, it is possible to obtain strong negative dispersion without absorption in the central resonance structure of the dispersion spectrum [28].…”

“…In the second case, the coherent driving is two-photon process as a one-step process while the two signal fields are produced step by step by a pair of one-photon processes [32]. In fact, the systems with coherent driving on the probe transitions can be less sensitive to Doppler broadening in an appropriate arrangement of both the driving and probe fields [23,27]. To our knowledge, there has been no report on the dispersive properties of driven three-level medium in the cascade configuration.…”