Related papers: Amplitude and phase control of gain without invers…
Transparent media exhibiting anomalous dispersion have been of considerable interest since Wang, Kuzmich, and Dogariu [Nature {\bf 406}, 277 (2000)] first observed light propagate with superluminal and negative group velocities without…
We propose a scheme for realizing broadband and tunable transmission non-reciprocity by utilizing two-photon near-resonant transitions in thermal atoms as single-photon far-detuned transitions can be eliminated. Our basic idea is to largely…
We study, in the framework of open quantum systems, the geometric phase acquired by a uniformly accelerated two-level atom undergoing nonunitary evolution due to its coupling to a bath of fluctuating vacuum electromagnetic fields in the…
An effective Hamiltonian describing interaction between generic "fast" and a "slow" systems is obtained in the strong interaction limit. The result is applied for studying the effect of quantum phase transition as a bifurcation of the…
We theoretically study the carrier-envelope phase dependent inversion generated in a two-level system by excitation with a few-cycle pulse. Based on the invariance of the inversion under time reversal of the exciting field, parameters are…
We report the phase control of spatial interference of resonance fluorescence from two duplicated two-level atoms, driving by two orthogonally polarized fields. In this closed-loop system, the relative phase is of crucial importance to the…
We show that atoms from wide velocity interval can be concurrently involved in Doppler-free two-photon resonant far from frequency degenerate four-wave mixing with the aid of auxiliary electromagnetic field. This gives rise to substantial…
The reflection spectrum of a probe light in a -type three-level atomic system coupled by an off-resonant standing-wave is investigated experimentally and theoretically. We show that the maximum value of reflection coefficient occurs when…
The phase diagrams and transitions of nonequilibrium systems with multiplicative noise are studied theoretically. We show the existence of both strong and weak-coupling critical behavior, of two distinct active phases, and of a nonzero…
Quantum coherent properties of electrons can be studied in Aharonov-Bohm (AB) interferometers. We investigate both experimentally and theoretically the transmission phase evolution in a four-terminal quasi-one-dimensional AlGaAs/GaAs-based…
For a one-dimensional electron-phonon system we consider the photon absorption involving electronic excitations within the pseudogap energy range. In the framework of the adiabatic approximation for the electron - phonon interactions these…
Parity-time (PT) symmetry and broken in micro/nano photonic structures have been investigated extensively as they bring new opportunities to control the flow of light based on non-Hermitian optics. Previous studies have focused on the…
The framework of quantum invariants is an elegant generalization of adiabatic quantum control to control fields that do not need to change slowly. Due to the unavailability of invariants for systems with more than one spatial dimension, the…
Optical control is achieved on the excited state energy transfer between spatially separated donor and acceptor molecules, both coupled to the same optical mode of a cavity. The energy transfer occurs through the formed hybrid polaritons…
The influence of dispersion-less quantum optical phonons on the phase diagram of a quarter-filled Hubbard chain is studied using the Density-matrix renormalization group technique. The ground state phase diagram is obtained for frequencies…
Well controlled nonlinear interactions between light field pulses and single atoms could be used to implement optical quantum information technologies based on qubits encoded in superpositions of coherent states of light. Here, we…
We discuss a many-particle quantum system, which is obtained by adding some nonhermitian but PT (i.e. combined parity and time reversal) invariant interaction to the $A_{N-1}$ rational Calogero model without confining potential. This model…
The interband polarizations induced by two phase-locked pulses in a semiconductor show strong interference effects depending on the time tau_1 separating the pulses. The four-wave mixing signal diffracted from a third pulse delayed by tau…
Based on a microscopic many-particle theory, we predict large optical gain in the probe and background-free four-wave mixing directions caused by excitonic instabilities in semiconductor quantum wells. For a single quantum well with…
The optical response of a heavily doped quantum well, with two occupied subbands, has been investigated as a function of the electronic density. It is shown that the two optically active transitions are mutually coupled by dipole-dipole…