Europhys. Lett.
Volume 72, Number 4, November 2005
Page(s) 618 - 623
Section Condensed matter: electronic structure, electrical, magnetic, and optical properties
Published online 14 October 2005
Europhys. Lett., 72 (4), pp. 618-623 (2005)
DOI: 10.1209/epl/i2005-10282-0

Novel approach to nonlinear susceptibility in semiconductors

M. Combescot1, O. Betbeder-Matibet1, K. Cho2 and H. Ajiki2

1  INSP, CNRS, Université Pierre et Marie Curie and Université Denis Diderot Campus Boucicaut - 140 rue de Lourmel, 75015 Paris, France
2  Graduate School of Engineering Science, Osaka University - Machikaneyama Toyonaka 560-8531, Japan

received 2 February 2005; accepted in final form 22 September 2005
published online 14 October 2005

We here propose a new procedure to derive a general expression of the third-order susceptibility valid for any semiconductor Hamiltonian. It relies on our theory for composite exciton many-body effects which is quite appropriate to this problem since all optical nonlinearities in semiconductors come from exchange scatterings with the virtual excitons coupled to photons. Our expression of $\chi^{(3)}$ is sample volume free, as physically expected. It also contains a Pauli term (exchange without Coulomb) which is missed by all bosonized exciton approaches. This term, dominant at large detuning, is a direct manifestation of the exciton composite nature.

71.35.-y - Excitons and related phenomena.

© EDP Sciences 2005