Wednesday, September 9, 2009

Sept. 10, 2009

LF12003

Single-Electronic Radio-Frequency Refrigerator

We demonstrate experimentally that a hybrid single-electron transistor with superconducting leads and a normal-metal island can be refrigerated by an alternating voltage applied to the gate electrode. The simultaneous measurement of the dc current induced by the rf gate through the device at a small bias voltage serves as an in situ thermometer.


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Accepted PRL

Atomtronic circuits of diodes and transistors

We illustrate that open quantum systems composed of neutral, ultracold atoms in one dimensional optical lattices can exhibit behavior analogous to semiconductor electronic circuits. A correspondence is demonstrated for bosonic atoms, and the experimental requirements to realize these devices are established. The analysis follows from a derivation of a quantum master equation for this general class of open quantum systems.