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Current hysteresis and memory effect in a molecular quantum dot with strong electron-vibron interaction

A. S. Alexandrov·A. M. Bratkovsky
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Abstract

Theory of current hysteresis for tunneling through a molecular quantum dot (MQD) with strong electron-vibron interactions and attractive electron-electron correlations is developed. The dot is modeled as a d-fold degenerate energy level weakly coupled to the leads. The effective attractive interaction between polarons in the dot results in a "switching" phenomenon in the current-voltage characteristics when d>2, in agreement with the results for the phenomenological negative-U model. The degenerate MQD with strong electron-vibron coupling has two stable current states in certain interval of the bias voltage below some critical temperature.

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A. S. Alexandrov, A. M. Bratkovsky. 2002-12-18. Current hysteresis and memory effect in a molecular quantum dot with strong electron-vibron interaction. https://doi.org/10.1103/physrevb.67.235312

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