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Effects of Polaron Formation in Semiconductor Quantum Dots on Transport Properties

Tomoki Tasai·Mikio Eto
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Abstract

We theoretically examine the effects of polaron formation in quantum dots on the transport properties. When a separation between two electron-levels in a quantum dot matches the energy of the longitudinal optical (LO) phonons, the polarons are strongly formed. The Rabi splitting between the levels is observable in a peak structure of the differential conductance G as a function of the bias voltage. The polaron formation suppresses the peak height of G, which is due to the competition between the resonant tunneling (resonance between a level in the dot and states in the leads) and the polaron formation (Rabi oscillation between two levels in the dot). G shows a sharp dip at the midpoint between the split peaks. This is attributable to the destructive interference between bonding and anti-bonding states in a composite system of electrons and phonons.

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Tomoki Tasai, Mikio Eto. 2003-04-10. Effects of Polaron Formation in Semiconductor Quantum Dots on Transport Properties. https://doi.org/10.1143/jpsj.72.1495

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