Selective Engineering for Preparing Entangled Steady States in Cavity QED Setup

Abstract

We propose a dissipative scheme to prepare maximally entangled steady states in cavity QED setup, consisting of two two-level atoms interacting with the two counter-propagating whispering-gallery modes (WGMs) of a microtoroidal resonator. Using spontaneous emission and cavity decay as the dissipative quantum dynamical source, we show that the steady state of this system can be steered into a two-atom single state as well as into a two-mode single state. We probed the compound system with weak field coupled to the system via a tapered fiber waveguide, finding it is possible to determine whether the two atoms or two modes are driven to a maximally entangled state. Through the transmission and reflection measurements, without disturbing the atomic state, when the cavity modes are being driven, or without disturbing the cavity field state, when a single atom being driven, one can get the information about the maximal entanglement. We also investigated for both subsystem, two-atom and two-mode states, the entanglement generation and under what conditions one can transfer entanglement from one subsystem to the other. Our scheme can be selectively used to prepare both maximally entangled atomic state as well as maximally entangled cavity-modes state, providing an efficient method for quantum information processing.

Rabi Oscillations, Entanglement and Teleportation in the Anti-Jaynes-Cummings Model

“…In the present work we consider an interesting case of quantum teleportation by applying entanglement swapping protocol (teleportation of entanglement) [38] [39] [40] [41] where the teleported state is itself entangled. The state we want to teleport is a two-atom maximally entangled state in which we have assigned subscripts to distinguish the atomic qubit states in the form [42] ( )…”

Generation of Entanglement between Two Two-Level Atoms Coupled to a Microtoroidal Cavity Via Thermal Field

“…In addition, we consider that there is a direct coupling between the two WGMs due to backscattering induced by cavity imperfections. According to the above scheme, the Hamiltonian of the system can be written in the form [24][25][26]:…”

“…The last two terms take into account the atom-atom coupling via dipole-dipole interaction and the coupling between the two modes, respectively. For the sake of simplicity, we assume that the atomic transition frequency of each atom is in resonance with the cavity (ω i eg = ω c = ω) and in the frame of the interaction representation with respect to H 0 = ∑ i=1,2 (hω/2)σ i z +hω(â †â +b †b ), the interaction Hamiltonian, in rotating wave approximation (RWA) is given by [24][25][26]:…”

Generation and transfer of entangled states between two connected microtoroidal cavities: Analysis of different types of coupling

“…For instance, the performance of tasks such as quantum teleportation in a quantum network, depends on both the control of entanglement generation and the transfer of entangled states between distant parties [6]. Several theoretical and experimental works have shown that cavity QED systems promote an efficient route towards the generation and distribution of entanglement [7][8][9][10]. In [11], the authors have demonstrated a process of entanglement transfer engineering, where two remote qubits interact with an entangled two-mode continuousvariable field.…”