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Limit cycle theory of temporal current self-oscillations in sequential tunneling of superlattices

X. R. Wang·Z. Z. Sun·S. Q. Duan·Shi-dong Wang
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Abstract

A unified theory of the temporal current self-oscillations is presented. We establish these oscillations as the manifestations of limit cycles, around unstable steady-state solutions caused by the negative differential conductance. This theory implies that both the generation and the motion of an electric-field domain boundary are universal in the sense that they do not depend on the initial conditions. Under an extra weak ac bias with a frequency $ω_{ac}$, the frequency must be either $ω_{ac}$ or an integer fractional of $ω_{ac}$ if the tunneling current oscillates periodically in time, indicating the periodic doubling for this non-linear dynamical system

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X. R. Wang, Z. Z. Sun, S. Q. Duan, Shi-dong Wang. 2002-11-21. Limit cycle theory of temporal current self-oscillations in sequential tunneling of superlattices. https://arxiv.org/abs/cond-mat/0211306

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