Direct Observation of the Photon Suppression of Electronic Shot Noise in a QPC

Eva Zakka-Bajjani (1) , Julien Segala (1) , Fabien Portier (1) , Patrice Roche (1) , Christian D.C. Glattli (1) , Antonella Cavanna (2) , Yong Jin (2)

1 SPEC - UMR3680 - Service de physique de l'état condensé
2 LPN - Laboratoire de photonique et de nanostructures

We report on direct measurements of the electronic shot noise of a Quantum Point Contact (QPC) at frequencies in the range 4-8GHz. 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 QPC drain-source voltage are comparable to the photon energy at the observation frequency, leading to observation of the shot noise suppression when the photon energy exceeds the maximum energy of injected electrons. The measurements provide the first direct comparison to the high frequency shot noise scattering theory without adjustable parameters.

Mots clés: Shot Noise; High Frequency; Quantum Point Contact

Domaines: Systèmes mésoscopiques et effet Hall quantique [cond-mat.mes-hall]

Eva Zakka-Bajjani, Julien Segala, Fabien Portier, Patrice Roche, Christian D.C. Glattli, et al.. Direct Observation of the Photon Suppression of Electronic Shot Noise in a QPC. 2007. ⟨hal-00140551v2⟩