Instantaneous processing of "slow light": amplitude-duration control, storage, and splitting

Nonadiabatic change of the control field or of the low-frequency coherence allows for an almost instantaneous change of the signal field propagating in a thick resonant absorber where electromagnetically induced transparency is realized. This finding is applied for the storage and retrieval of the signal, for the creation of a signal copy and separation of this copy from the original pulse without its destruction.Comment: 9 pages, 1 figure, submitted to PRL on 18, December, 200

Adiabatic following criterion, estimation of the nonadiabatic excitation fraction and quantum jumps

An accurate theory describing adiabatic following of the dark, nonabsorbing state in the three-level system is developed. An analytical solution for the wave function of the particle experiencing Raman excitation is found as an expansion in terms of the time varying nonadiabatic perturbation parameter. The solution can be presented as a sum of adiabatic and nonadiabatic parts. Both are estimated quantitatively. It is shown that the limiting value to which the amplitude of the nonadiabatic part tends is equal to the Fourier component of the nonadiabatic perturbation parameter taken at the Rabi frequency of the Raman excitation. The time scale of the variation of both parts is found. While the adiabatic part of the solution varies slowly and follows the change of the nonadiabatic perturbation parameter, the nonadiabatic part appears almost instantly, revealing a jumpwise transition between the dark and bright states. This jump happens when the nonadiabatic perturbation parameter takes its maximum value.Comment: 33 pages, 8 figures, submitted to PRA on 28 Oct. 200

MÖSSBAUER EFFECT STUDY OF THE ANNEALING OF 57[MATH]AL, IMPLANTED AT 4.2K

No abstract availabl

POSTIMPLANTATION EFFECTS ON 133[MATH]W

No abstract availabl

Level mixing induced transparency II: Different transition probabilities of the crossing lines

In one of our previous papers (R.N. Shakhmuratov et al. Appl. Phys. B. 81, 883 (2005)) we presented a new type of spatiotemporal interference of gamma radiation propagating in a resonant medium. The excitation scheme consists of two identical V-schemes, each being formed by one type of the transition: one is induced only by the left circular polarized field and the other by the right circular polarized field. The coupling of these V-schemes through level crossing allows resonant scattering of a photon in the forward direction with a change of its polarization. As a result the radiation field, which is resonant with a transition from the ground state to one of the two sublevels of the excited state, develops in a particular combination of radiation fields with left and right circular polarizations, called a normal mode. This combination is much less absorbed in subsequent layers of the absorber. For identical V-schemes, the structure of the modes is fairly simple. In this paper, we show that a similar reduction of absorption is realized for non-identical V-schemes, differing in transition strengths. The structure of the normal modes is found and they have a more complicated form. This general case is actually realized in a level crossing experiment in gamma optics.info:eu-repo/semantics/publishe

Coherent forward scattering of a single photon wave packet in a resonant medium

The propagation of a single photon wave packet in a thick resonant medium was studied theoretically and experimentally. The well-known acceleration of wave packet decay was observed upon wave packet exiting from a medium with single resonant absorption line. It was found that in a medium with two closely spaced absorption lines, the restoration of the photon wave packet is observed after the acceleration of decay. © 2010 Allerton Press, Inc

Coherent forward scattering of a single photon wave packet in a resonant medium

The propagation of a single photon wave packet in a thick resonant medium was studied theoretically and experimentally. The well-known acceleration of wave packet decay was observed upon wave packet exiting from a medium with single resonant absorption line. It was found that in a medium with two closely spaced absorption lines, the restoration of the photon wave packet is observed after the acceleration of decay. © 2010 Allerton Press, Inc

Bulletin administratif du Cambodge

05 octobre 19441944/10/05 (A43,N40)-1944/10/05 (A43,N48)