On the quantum link for transport of logic states

A novel approach for representing logic states in the quantum nodes and transferring the states from one node to another is proposed. Both transmit and receive nodes consist of a rubidium atom (87Rb) placed at the center of a two-mode cavity. Representation of logic states by two subspaces of the space of 87Rb atom hyperfine states eliminates the need for the transmitting node to change logic state during logic transfer through Raman process. The atom is excited by simultaneous application of two laser beams – one for each subspace. Based on the logic state, the atom emits a photon of appropriate frequency and polarization through Raman process within the corresponding subspace. The emitted photon leaks out of the cavity, reaches the receiving node, and initiates logic dependent transitions there. A simulation platform is developed through the system Hamiltonians for transmit and receive nodes followed by the formulation of the time evolution of the density matrices for the nodes. The efficacy of the simulation approach is emphasized.