TY - JOUR
T1 - Maximization of thermal entanglement of arbitrarily interacting two qubits
AU - Kuwahara, Tomotaka
AU - Hatano, Naomichi
PY - 2011/6/10
Y1 - 2011/6/10
N2 - We investigate the thermal entanglement of interacting two qubits. We maximize it by tuning a local Hamiltonian under a given interaction Hamiltonian. We prove that the optimizing local Hamiltonian takes a simple form which does not depend on the temperature and that the corresponding optimized thermal entanglement decays as 1/(TlnT) at high temperatures. We also find that at low temperatures the thermal entanglement is maximum without any local Hamiltonians and that the second derivative of the maximized thermal entanglement changes discontinuously at the boundary between the high- and low-temperature phases.
AB - We investigate the thermal entanglement of interacting two qubits. We maximize it by tuning a local Hamiltonian under a given interaction Hamiltonian. We prove that the optimizing local Hamiltonian takes a simple form which does not depend on the temperature and that the corresponding optimized thermal entanglement decays as 1/(TlnT) at high temperatures. We also find that at low temperatures the thermal entanglement is maximum without any local Hamiltonians and that the second derivative of the maximized thermal entanglement changes discontinuously at the boundary between the high- and low-temperature phases.
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U2 - 10.1103/PhysRevA.83.062311
DO - 10.1103/PhysRevA.83.062311
M3 - Article
AN - SCOPUS:79961072099
VL - 83
JO - Physical Review A - Atomic, Molecular, and Optical Physics
JF - Physical Review A - Atomic, Molecular, and Optical Physics
SN - 1050-2947
IS - 6
M1 - 062311
ER -