laboratoire pierre aigrain
électronique et photonique quantiques
laboratoire pierre aigrain

Séminaire - 01/12/2008

I. A. Shelykh (St. Petersburg State Polytechnical University, Russia and University of Iceland, Iceland)
Spin-optronics : polarization of emission from quantum microcavities

Spin-optronics is a new emerging research area, which combines studies of spin and optical polarisation effects in solids with the ultimate goal of creating quantum optoelectronic devices [1]. This is an interdisciplinary research field at the crossroads of fundamental physics, optoelectronics, and nano-technology. In spin-optronics, the information which is ultimately carried by the polarisation of photons, can be encoded in the confined spin state of carriers, manipulated on the nanoscale, and redelivered in the form of polarised photons. With respect to optics, spin-optronics has the advantage of being able to use well controlled carrier interactions occurring in nanostructures. With respect to ‘spintronics’, it has the advantage of strongly reducing the dramatic impact of carrier spin relaxation or decoherence, which has severely limited the achievement or the functionality of any working semiconductor-based spintronic devices.
In the present work we present recent results on theoretical description of spin and polarization dynamics in quantum microcavities- photonic structures designed to enhance the light-matter interaction. In strong coupling regime the normal modes of the system are cavity polaritons that are half-exciton, half-photon quasiparticles. When optically created, polaritons inherit the spin and dipole moment from the exciting light. However, from the very beginning of their life in a microcavity, polaritons start changing their spin state under effect of effective magnetic fields of different nature and scattering which makes pseudospin dynamics of exciton-polaritons rich and complex [2]. This can be used for the creation novel spinoptronic components such as quantum beam splitters, polarization filters and efficient sources of the entangled photon pairs [3]

[1] I. Shelykh, K.V. Kavokin, A.V. Kavokin, G. Malpuech, P. Bigenwald ,H. Deng, G. Weihs, Y. Yamamoto, Phys. Rev. B, 70, 035320 (2004)
[2] I.A. Shelykh, T.C.H. Liew, A.V. Kavokin, Phys. Rev. Lett 100, 116401 (2008)
[3] R. Johne, N.A Gippius, G. Pavlovic, D.D. Solnyshkov, I.A. Shelykh and G. Malpuech, Phys. Rev. Lett. 100, 240404 (2008)