相关论文: Multimode quantum limits to the linewidth of an at…
A fundamental tenet of quantum mechanics is that measurements change a system's wavefunction to that most consistent with the measurement outcome, even if no observer is present. Weak measurements produce only limited information about the…
The nonlinear photon-photon interaction mediated by a single two-level atom is studied theoretically based on a one-dimensional model of the field-atom interaction. This model allows us to determine the effects of an atomic nonlinearity on…
We study the quantum interference between the excitation pathways in a three-level $\Lambda$-type atom interacting with two short laser pulse trains under the conditions of electromagnetically induced transparency. The probability amplitude…
The problem of the two-level atom laser is studied analytically. The steady-state solution is expressed as a continued fraction, and allows for accurate approximation by rational functions. Moreover, we show that the abrupt change observed…
Formation of atomic pairs by the dissociation of a molecular condensate or by inelastic collisions in an atomic condensate due to a time-dependent curve crossing process is studied beyond the mean-field approximation. The number of atoms…
We hypothesize that a charged particle in unbounded vacuum can be substantially accelerated by a force linear in the electric field of a propagating electromagnetic wave only if the accelerating field is capable of bringing the particle to…
Different laser devices working as ``atom diodes'' or ``one-way barriers'' for ultra-cold atoms have been proposed recently. They transmit ground state level atoms coming from one side, say from the left, but reflect them when they come…
We investigate the energy of a theory with a unit vector field (the "aether") coupled to gravity. Both the Weinberg and Einstein type energy-momentum pseudotensors are employed. In the linearized theory we find expressions for the energy…
We present a theoretical study of strong laser-atom interactions, when the laser field parameters are subjected to random processes. The atom is modelled by a two-level and three-level systems, while the statistical fluctuations of the…
Quantum theory of the intraband resonant tunneling of a Bose-Einstein condensate loaded in a twodimensional optical lattice is considered. It is shown that the phenomena of quantum collapse and revival can be observed in the fully quantum…
Optical pulses propagating in multimode optical fibers are affected by linear disorder and nonlinearity, and experience chaotic exchange of power among modes. On the other hand, complex systems can attain steady states characterized by…
Semiclassical equations of lasing dynamics are re-derived for a lasing medium in a cavity with a spatially non-uniform dielectric constant. It is shown that the non-uniformity causes a radiative coupling between modes of the empty cavity.…
We study non-classical and spectral properties of a strongly driven single-atom laser engineered within a photonic crystal that facilitates a frequency-dependent reservoir. In these studies, we apply a dressed atom model approach to derive…
Nanoscale lasers sustain few optical modes so that the fraction of spontaneous emission $\beta$ funnelled into the useful (lasing) mode is high (of the order of few 10$^{-1}$) and the threshold, which traditionally corresponds to an abrupt…
We report on an investigation of the beam profile of an atom laser extracted from a magnetically trapped $^{87}$Rb Bose-Einstein condensate. The transverse momentum distribution is magnified by a curved mirror for matter waves and a…
A quantum phase transition from the miscible to the immiscible phase of a quasi-one-dimensional binary Bose-Einstein condensate is driven by ramping down the coupling amplitude of its two hyperfine states. It results in a random pattern of…
We simulate three experimental methods which could be realized in the laboratory to probe the band excitation energies and the momentum distribution of a Bose-Einstein condensate inside an optical lattice. The values of the excitation…
We study both numerically and analytically the possibility of using an adiabatic passage control method to construct a Mach-Zehnder interferometer (MZI) for Bose-Einstein condensates (BECs) in the time domain, in exact one-to-one…
The intra-band tunneling of a Bose-Einstein condensate between three degenerate high-symmetry X-points of the Brillouin zone of a cubic optical lattice is studied in the quantum regime by reduction to a three-mode model. The mean-field…
We demonstrate an atom laser using all-optical techniques. A Bose-Einstein condensate of rubidium atoms is created by direct evaporative cooling in a quasistatic dipole trap realized with a single, tightly focused CO$_{2}$-laser beam. An…