Bohmian quantum mechanical and classical Lyapunov exponents for kicked rotor

Using de Broglie-Bohm approach to quantum theory, we show that the kicked rotor at quantum resonance exhibits quantum chaos for the control parameter K above a threshold. Lyapunov exponents are calculated from the method of Benettin et al. for bounded systems for both the quantum and classical kicked rotor. In the chaotic regime we find stability regions for control parameters equal to even and odd multiples of pi, but the quantum regions are only remnants of the classical ones. (c) 2006 Elsevier Ltd. All rights reserved.