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Register a new userParameter scaling in a novel measure of quantum-classical difference for decohering chaotic systems
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Added by
Arjendu K. Pattanayak
Publication date
2009
fields
Physics
and research's language is
English
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In this paper we introduce a diagnostic for measuring the quantum-classical difference for open quantum systems, which is the normalized size of the quantum terms in the Master equation for Wigner function evolution. For a driven Duffing oscillator, this measure shows remarkably precise scaling over long time-scales with the parameter $zeta_0=hbar^2/D$. We also see that, independent of $zeta_0$ the dynamics follows a similar pattern. For small $zeta_0$ all of our curves collapses to essentially a single curve when scaled by the maximum value of the quantum-classical difference. In both limits of large and small $zeta_0$ we see a saturation effect in the size of the quantum-classical difference; that is, the instantaneous difference between quantum and classical evolutions cannot be either too small or too large.
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