Quantum-mechanical nonperturbative response of driven chaotic mesoscopic systems.

Consider a time-dependent Hamiltonian H(Q,P;x(t)) with periodic driving x(t) = Asin(Omegat). It is assumed that the classical dynamics is chaotic, and that its power spectrum extends over some frequency range |omega|<omega(cl). Both classical and quantum-mechanical (QM) linear response theory (LRT) predict a relatively large response for Omega<omega(cl), and a relatively small response otherwise, independent of the driving amplitude A. We define a nonperturbative regime in the (Omega,A) space, where LRT fails, and demonstrate this failure numerically. For A>A(prt), where A(prt) approximately Planck's over 2pi, the system may have a relatively strong response for Omega>omega(cl) due to QM nonperturbative effect.