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arXiv · 1301.5776

Bound states in the continuum driven by AC fields

C. González-Santander·P. A. Orellana·F. Domínguez-Adame
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Abstract

We report the formation of bound states in the continuum driven by AC fields. This system consists of a quantum ring connected to two leads. An AC side-gate voltage controls the interference pattern of the electrons passing through the system. We model the system by two sites in parallel connected to two semi-infinite lattices. The energy of these sites change harmonically with time. We obtain the transmission probability and the local density of states at the ring sites as a function of the parameters that define the system. The transmission probability displays a Fano profile when the energy of the incoming electron matches the driving frequency. Correspondingly, the local density of states presents a narrow peak that approaches a Dirac delta function in the weak coupling limit. We attribute these features to the presence of bound states in the continuum.

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C. González-Santander, P. A. Orellana, F. Domínguez-Adame. 2013-01-24. Bound states in the continuum driven by AC fields. https://doi.org/10.1209/0295-5075%2F102%2F17012

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