TY - JOUR
T1 - Origin of branch points in the spectrum of PT -symmetric periodic potentials
AU - Chang, Ching Hao
AU - Wang, Shi Ming
AU - Hong, Tzay Ming
PY - 2009/10/6
Y1 - 2009/10/6
N2 - There exist multiple branch points in the energy spectrum for some PT -symmetric periodic potentials, where the real eigenvalues turn into complex ones. By studying the transmission amplitude for a localized complex potential, we elucidate the physical origin of the breakdown of the perturbation method and Born approximation. Most importantly, we derive an analytic criterion to determine why, when, and where the bifurcation will occur.
AB - There exist multiple branch points in the energy spectrum for some PT -symmetric periodic potentials, where the real eigenvalues turn into complex ones. By studying the transmission amplitude for a localized complex potential, we elucidate the physical origin of the breakdown of the perturbation method and Born approximation. Most importantly, we derive an analytic criterion to determine why, when, and where the bifurcation will occur.
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U2 - 10.1103/PhysRevA.80.042105
DO - 10.1103/PhysRevA.80.042105
M3 - Article
AN - SCOPUS:70349897387
SN - 1050-2947
VL - 80
JO - Physical Review A - Atomic, Molecular, and Optical Physics
JF - Physical Review A - Atomic, Molecular, and Optical Physics
IS - 4
M1 - 042105
ER -