Eur. Phys. J. D 61, 241-247 (2011)
https://doi.org/10.1140/epjd/e2010-00233-2

Smoothed Wigner-distributions, decoherence, and the temperature-dependence of the classical-quantum frontier

¹ Departamento de Física, Universidad Católica del Norte, Av. Angamos 0610, Antofagasta, Chile
² Instituto de Física La Plata-CCT-CONICET, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, C.C. 727, (1900), La Plata, Argentina

Corresponding author: ^a fpennini@ucn.cl

Received: 29 April 2010
Revised: 28 July 2010
Published online: 14 September 2010

Abstract

We discuss the strange behavior at T = 0 of the phase-space Wigner distribution of the harmonic oscillator with the help of the purely quantal concepts of participation ratio of a mixed state and decoherence parameter. We also show that Wigner distribution-smoothing yields interesting insights, specially in the pathological instance in which the Wigner-Fano factor diverges. The associated decoherence parameter also sheds some light on temperature-dependence of the classical-quantum frontier.