Dresden 2014 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

TT: Fachverband Tiefe Temperaturen

TT 18: Transport: Fluctuations and Noise

TT 18.2: Talk

Monday, March 31, 2014, 15:15–15:30, HSZ 204

Non-Gaussian noise- and plasmon-assisted over-bias light emission from tunnel contacts — •Fei Xu, Cecilia Holmqvist, and Wolfgang Belzig — Fachbereich Physik, Universität Konstanz, Konstanz, Germany

Understanding tunneling from an atomically sharp tip to a metallic surface requires to account for interactions on a nanoscopic scale. Inelastic tunneling of electrons gives rise to the emission of photons, whose energies should intuitively be limited by the applied bias voltage eV. However, experiments [1,2] indicate that more complex processes involving the interaction of electrons with plasmons lead to photon emission with over-bias energies. We propose a model of this observation in analogy to the dynamical Coulomb blockade, originally developed to treat the electronic environment in mesoscopic circuits. We explain the experimental finding quantitatively by correlated tunneling of two electrons interacting with an RCL circuit to model the local plasmon mode. We show that the non-Gaussian statistics of the tunneling dynamics of the electrons is essential to describe the over bias emission .
G. Schull et al., PRL 102, 057401 (2009)
N. L. Schneider et al., PRL 105, 026601 (2010)