Quantum dynamics of spatial decoherence of two atoms in a ring cavity

Abstract

We study the spatial decoherence dynamics for the relative position of two atoms in a singlemode ring cavity. We find that the spatial decoherence of the two atoms depends strongly on their relative position. Taking into account the spatial degrees of freedom, we investigate the entanglement dynamics of the internal states of the two atoms. It is shown that the entanglement decays to almost zero in a finite time, and the disentanglement time depends on the width of the wave packets describing the atomic spatial distribution.

Scheme for generating the singlet state of three atoms trapped in distant cavities coupled by optical fibers

“…In the short fiber limit, essentially only one fiber mode interacts with the cavity modes. In this case the interaction Hamiltonian of the atom-cavity-fiber system in the interaction picture is given by [39,40] …”

“…Ω j is the coupling coefficient of the jth classical field, ν is the coupling strength between the cavity mode and the fiber mode, and g j is the coupling constant between the jth atom and cavity mode. Introducing the new bosonic modes [39,41] …”

The Influences of the Selective Atomic Measurement on Entanglement Properties in the System of Three Atoms Trapped in Two Distant Cavities Connected by an Optical Fiber

“…In recent years, much attention has been paid to the study of the possibility of quantum information processing realized via optical fibers [12][13][14][15][16]. Pelizzari [17] proposed a scheme which allows for reliable transfer of quantum information between two atoms in distant cavities coupled by an optical fiber.…”

Scattering of coherent pulses on a two-level system—single-photon generation

“…Systems with (artificial) atoms coupled to a one-dimensional continuum of photonic modes have been theoretically analyzed in [7][8][9][10][11][12][13][14] and experimental impementations in cQED include [15][16][17][18][19][20][21][22][23][24]. In order to use propagating photons for quantum information, several tools for manipulation, like single-photon sources and detectors, are needed.…”

“…In this paper, we examine the possibilities of constructing a non-cavity based singlephoton source. Resonant scattering of coherent states on a two-level system (TLS) has been shown theoretically [9,11,12,35] and experimentally [20] to result in a photon number redistribution, with the single-photon probability being enhanced (suppressed) in the reflected (transmitted) field. The idea is to exploit this fact to, by choosing an appropriate input pulse, use the TLS as an on-demand single-photon source.…”