16 research outputs found
Enhanced Nonlinear Generation in a Three-Level Medium with Spatially Dependent Coherence
We consider a method for efficient parametric generation of a laser pulse. A
single laser field is injected to a three-level medium which has two lower
states and one excited state. The lower states are prepared initially in a
position-dependent coherent superposition state. It is shown that by proper
choice of the position dependence of the superposition along the direction of
propagation, the incoming field can be converted completely to a new field.Comment: Revtex4 document, 3 pages, 2 figure
Studies of group velocity reduction and pulse regeneration with and without the adiabatic approximation
We present a detailed semiclassical study on the propagation of a pair of
optical fields in resonant media with and without adiabatic approximation. In
the case of near and on resonance excitation, we show detailed calculation,
both analytically and numerically, on the extremely slowly propagating probe
pulse and the subsequent regeneration of a pulse via a coupling laser. Further
discussions on the adiabatic approximation provide many subtle understandings
of the process including the effect on the band width of the regenerated
optical field. Indeed, all features of the optical pulse regeneration and most
of the intricate details of the process can be obtained with the present
treatment without invoke a full field theoretical method. For very far off
resonance excitation, we show that the analytical solution is nearly detuning
independent, a surprising result that is vigorously tested and compared to
numerical calculations with very good agreement.Comment: 13 pages, 15 figures, submitted to Phys. Rev.
From Storage and Retrieval of Pulses to Adiabatons
We investigate whether it is possible to store and retrieve the intense probe
pulse from a -type homogeneous medium of cold atoms. Through numerical
simulations we show that it is possible to store and retrieve the probe pulse
which are not necessarily weak. As the intensity of the probe pulse increases,
the retrieved pulse remains a replica of the original pulse, however there is
overall broadening and loss of the intensity. These effects can be understood
in terms of the dependence of absorption on the intensity of the probe. We
include the dynamics of the control field, which becomes especially important
as the intensity of the probe pulse increases. We use the theory of adiabatons
[Grobe {\it et al.} Phys. Rev. Lett. {\bf 73}, 3183 (1994)] to understand the
storage and retrieval of light pulses at moderate powers.Comment: 15 pages, 7 figures, typed in RevTe
Quantum memory for photons: I. Dark state polaritons
An ideal and reversible transfer technique for the quantum state between
light and metastable collective states of matter is presented and analyzed in
detail. The method is based on the control of photon propagation in coherently
driven 3-level atomic media, in which the group velocity is adiabatically
reduced to zero. Form-stable coupled excitations of light and matter
(``dark-state polaritons'') associated with the propagation of quantum fields
in Electromagnetically Induced Transparency are identified, their basic
properties discussed and their application for quantum memories for light
analyzed.Comment: 13 pages, 6 figures, paragraph on photon echo adde
Propagation dynamics in an autoionization medium
Published versio
Transparency induced via decay interference
Published versio