The entropy of position and the spreading of wave packets

ANTON Z. CAPRI

Marian Grabowski

The spreading of free wave packets is expressed by means of the entropy of position for a certain class of states. Connection between such formulation and the usual treatment is discussed.

Antonio Zecca A

Corneliu Manescu, Jeffrey L. Krause, Klaus B. Møller +1 more

We investigate the focusing, that is, the reversing of spreading of continuum wave packets created with chirped laser pulses in the weak-field limit. Focusing can be accomplished when a negative position−momentum correlation is created in the wave packet. Specializing to constant and linear (repulsive) potentials, we show analytically that in a constant potential wave packet spreading can be compensated with positively chirped laser pulses, whereas in the linear potential negatively chirped laser pulses are required, in the short-pulse limit. The analytical results for the linear potential are supported by numerical simulations. The results are discussed in the context of a classical model for wave packet focusing.

K. T. Hecht

Wei-Min Zhang, D.H. Feng

The spreading of a wave packet in various nonlinear external potentials with dissipation is studied. The dynamical description of this spreading is given by the use of the squeezed states and the semiquantal approach. We show that the position uncertainty of a Gaussian wave packet is dictated by quantum correlation and the behavior of its evolution can be vividly displayed. For various external potentials with dissipation, we find that the spreading of the wave packet is inevitably suppressed.