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A possible minimum toy model with negative differential capacitance for self-sustained current oscillation

Gang Xiong·Z. Z. Sun·X. R. Wang
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Abstract

We generalize a simple model for superlattices to include the effect of differential capacitance. It is shown that the model always has a stable steady-state solution (SSS) if all differential capacitances are positive. On the other hand, when negative differential capacitance is included, the model can have no stable SSS and be in a self-sustained current oscillation behavior. Therefore, we find a possible minimum toy model with both negative differential resistance and negative differential capacitance which can include the phenomena of both self-sustained current oscillation and $I-V$ oscillation of stable SSSs.

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Gang Xiong, Z. Z. Sun, X. R. Wang. 2006-02-16. A possible minimum toy model with negative differential capacitance for self-sustained current oscillation. https://arxiv.org/abs/cond-mat/0512370

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