Quantum dynamical phase transition in a system with many-body interactions

ERNESTO P. DANIELI; GONZALO A. ÁLVAREZ; H. M. PASTAWSKI

SOLID STATE COMMUNICATIONS

Elsevier

Año: 2007 vol. 141 p. 422 - 426

0038-1098

Quantum dynamical phase transition in a system with many-body interactions E. P. Danieli, G. A. Álvarez, P. R. Levstein and H. M. Pastawski Solid State Communications141, 422 (2007) cond-mat/0511639 Abstract: We introduce a microscopic Hamiltonian model of a two level system with many-body interactionswith an environment whose excitation dynamics is fully solved within the Keldysh formalism. Ifa particle starts in one of the states of the isolated system, the return probability oscillates withthe Rabi frequency w0. For weak interactions with the environment 1/tSE< 2w0, we find a slower oscillation whose amplitude decays with a rate 1/tphi = 1/(2tSE) However, beyond a finite critical interaction with the environment,1/tSE> 2w0 ,the decay rate becomes 1/ / !20 SE. The oscillation period diverges showing a quantum dynamical phase transition to a Quantum Zeno phase.