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arXiv · 1205.5882

Cooling a nanomechanical resonator by a triple quantum dot

Zeng-Zhao Li·Shi-Hua Ouyang·Chi-Hang Lam·J. Q. You
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Abstract

We propose an approach for achieving ground-state cooling of a nanomechanical resonator (NAMR) capacitively coupled to a triple quantum dot (TQD). This TQD is an electronic analog of a three-level atom in $Λ$ configuration which allows an electron to enter it via lower-energy states and to exit only from a higher-energy state. By tuning the degeneracy of the two lower-energy states in the TQD, an electron can be trapped in a dark state caused by destructive quantum interference between the two tunneling pathways to the higher-energy state. Therefore, ground-state cooling of an NAMR can be achieved when electrons absorb readily and repeatedly energy quanta from the NAMR for excitations.

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Zeng-Zhao Li, Shi-Hua Ouyang, Chi-Hang Lam, J. Q. You. 2012-05-26. Cooling a nanomechanical resonator by a triple quantum dot. https://doi.org/10.1209/0295-5075%2F95%2F40003

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