Vendredi 21 février 2014 à 10h15
Salle Datcha,

Electron waiting times in mesoscopic conductors

Géraldine Haack, Dahlem Center, Germany

Electronic transport through mesoscopic devices is known to be stochastic due to the quantum nature of the charge carriers. The noise power spectrum as well as the Full Counting Statistics provide important information when considering the number of transferred charges in the limit of long times. On the contrary, the waiting times distribution (WTD) between the detection of consecutive charge carriers has been recently investigated and shown to be powerful to understand the short time physics [1,2,3]. In this talk, I will first present our quantum derivation of the WTD, which allows us to express the WTD as a determinant formula. The WTD then shows to be an efficient statistical tool to probe both the coherence properties of the scatterer and the short-time correlations of the incoming train of particles. This will be illustrated by considering transport in a perfect one dimensional quantum channel with a quantum point contact. In this setup, the WTD exhibits a crossover from a Poisson statistics to the Wigner-surmise distribution. We then generalize our theory to take into account finite-temperature effects, multi-channels setups and scatterers with momentum-dependent transmission amplitudes like the Fabry-P'erot interferometer [4]. Finally, I will show how to express the WTD in terms of continuous matrix product states (cMPS). Given that the cMPS can be reconstructed from correlation functions, this might open a way on how to access the WTD in an experiment [5]. [1] T. Brandes, Ann. Phys. (Berlin) 17, 477 (2008). [2] M. Albert, C. Flindt and M. B"uttiker, Phys. Rev. Lett. 107, 086805 (2011). [3] M. Albert, G. Haack, C. Flindt and M. B"uttiker, Phys. Rev. Lett. 108, 186806 (2012). [4] G. Haack et al., in preparation. [5] Collaboration with R. H"ubener and J. Eisert, work in progress.