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arXiv · 0704.0907

Experimental Test of the High-Frequency Quantum Shot Noise Theory in a Quantum Point Contact

Eva Zakka-Bajjani·Julien Segala·Fabien Portier·Patrice Roche·Christian Glattli·Antonella Cavanna·Yong Jin
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Abstract

We report on direct measurements of the electronic shot noise of a quantum point contact at frequencies nu in the range 4-8 GHz. The very small energy scale used ensures energy independent transmissions of the few transmitted electronic modes and their accurate knowledge. Both the thermal energy and the quantum point contact drain-source voltage Vds are comparable to the photon energy hnu leading to observation of the shot noise suppression when $V_{ds}<hν/e$. Our measurements provide the first complete test of the finite frequency shot noise scattering theory without adjustable parameters.

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Eva Zakka-Bajjani, Julien Segala, Fabien Portier, Patrice Roche, Christian Glattli, Antonella Cavanna, Yong Jin. 2008-04-22. Experimental Test of the High-Frequency Quantum Shot Noise Theory in a Quantum Point Contact. https://doi.org/10.1103/physrevlett.99.236803

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