INSP - 4 place Jussieu - 75252 PARIS Cedex 05 - Corridor 22-32 - Second Floor, room 201

Fabien Portier - SPEC CNRS UMR 3680 - CEA Saclay

Abstract

A dc biased quantum conductor gives rise to current fluctuations, as a result of the granularity of charge carriers and the probabilistic character of quantum transport. Such current fluctuations may excite the surrounding electromagnetic modes, giving rise to an essentially unexplored regime of light-matter coupling at the quantum level. During this talk I will show that this light-matter coupling can be engineered on-chip giving rise not only to high detection efficiencies for the emitted radiation [1], but also to strong modifications of the transport properties of the conductor itself [2]. The resulting physics are already rich for the simplest case of tunnel junctions, where electrons tunnel stochastically across thin insulating barriers. I will show that tunnel junctions made from normal metals follow non-equilibrium fluctuation-dissipation relations linking the finite frequency dynamics and the photon emission rate to the dc I(V) characteristic [3]. And I will also show that the radiation emitted by a Josephson junction, a tunnel junction separating two superconducting electrodes, into two different electromagnetic modes exhibits non-classical power correlations.

References : [1] Altimiras et al., Appl. Phys. Lett. 103 , 212601 (2013). [2] Altimiras et al., Phys. Rev. Lett. 112, 236803 (2014). [3] Parlavecchio et al., to be published in Phys. Rev. Lett. (2015), arXiv:1409.6696. [4] Parlavecchio et al., in preparation.