When measuring quantum mechanical properties of charge transport in mesoscopic conductors, backaction effects occur. We consider a measurement setup with an elementary quantum circuit, composed of an inductance and a capacitor, as detector of the current flowing in a nearby quantum point contact. A quantum Langevin equation for the detector variable including backaction effects is derived. Differences with the quantum Langevin equation obtained in linear response are pointed out. In this last case, a relation between fluctuations and dissipation is obtained, provided that an effective temperature of the quantum point contact is defined.
|Numero di pagine||10|
|Rivista||Fortschritte der Physik|
|Stato di pubblicazione||Published - 2017|
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)
Valenti, D., Spagnolo, B., Magazzù, L., Martin, T., Paladino, E., Spagnolo, B., & Falci, G. (2017). Detector's quantum backaction effects on a mesoscopic conductor and fluctuation-dissipation relation. Fortschritte der Physik, 65, 1-10.