5 research outputs found
Entanglement Teleportation via Werner States
Transfer of entanglement and information is studied for quantum teleportation
of an unknown entangled state through noisy quantum channels. We find that the
quantum entanglement of the unknown state can be lost during the teleportation
even when the channel is quantum correlated. We introduce a fundamental
parameter of correlation information which dissipates linearly during the
teleportation through the noisy channel. Analyzing the transfer of correlation
information, we show that the purity of the initial state is important in
determining the entanglement of the replica state.Comment: 4pages, 3figure
Entanglement generation by adiabatic navigation in the space of symmetric multi-particle states
We propose a technique for robust and efficient navigation in the Hilbert
space of entangled symmetric states of a multiparticle system with externally
controllable linear and nonlinear collective interactions. A linearly changing
external field applied along the quantization axis creates a network of well
separated level crossings in the energy diagram of the collective states. One
or more transverse pulsed fields applied at the times of specific level
crossings induce adiabatic passage between these states. By choosing the timing
of the pulsed field appropriately, one can transfer an initial product state of
all N spins into (i) any symmetric state with n spin excitations and (ii) the
N-particle analog of the Greenberger-Horne-Zeilinger state. This technique,
unlike techniques using pulses of specific area, does not require precise
knowledge of the number of particles and is robust against variations in the
interaction parameters. We discuss potential applications in two-component Bose
condensates and ion-trap systems.Comment: 7 pages, 6 figure