Power fluctuations in an ac driven coherent conductor

Francesca Battista

Institute for Theory of Statistical Physics, RWTH Aachen University, Germany, JARA-Fundamentals of Future Information Technology

Tuesday, 04 February 2014, 10:15
Matfys library

Single particle sources are time-periodically driven devices emitting a controlled number of particles for each period. They are of key importance in research fields as metrology and quantum electron optics [1], where high emitting accuracy is required. The precision of these devices is limited by the fluctuations due to extra electron-hole excitations induced by the driving of the system itself. One of the possible experimental realizations of a single particles source is the application of a Lorentzian pulse to a conductor. In special cases [2] this creates an ideal noiseless quantized particle stream (Levitons) [3]. The experimental attempts to reach this ideal case have shown that adding one or more harmonic driving signal of different frequency reduces the current fluctuations [4,5]. The fluctuations related to the electron-hole excitations triggered the interest in the characteristics of the energy transport of these systems. Thus in order to complement the charge transport investigation [6] we study the energy transport properties of a coherent conductor when subjected to different signals. In particular we considered the contribution of the electron-hole like excitations to the heat current and the low frequency heat [7]. We finally relate these quantities to the power supplied to the system [7].

[1] J. P. Pekola et al., Rev. Mod. Phys. 85, 1421 (2013).
[2] J. Keeling et al., Phys. Rev. Lett. 97, 116403 (2006).
[3] J. Dubois et al., Phys. Rev. B 88, 085301 (2013).
[4] J. Gabelli and B. Reulet, Phys. Rev. B 87, 075403 (2013).
[5] J. Dubois et al., Nature 502, 659 (2013).
[6] M. Vanevic and W. Belzig, Phys. Rev. B 86, 241306 (2012).
[7] F. Battista, F. Haupt, J. Splesttoesser, in preparation.