| Autor: |
Canzler, T.W., Holfeld, C.P., Lyssenko, V.G., Whittaker, D.M., Köhler, K., Leo, K. |
| Zdroj: |
Physica Status Solidi (A) - Applications and Materials Science; March 2000, Vol. 178 Issue: 1 p39-44, 6p |
| Abstrakt: |
We report on the systematical investigation of Fano resonances in electrically biased semiconductor superlattices. In such quantum structures, Coulomb interaction couples discrete excitonic states of the Wannier-Stark ladder to continua of lower-lying subbands. In absorption these transitions show the typical asymmetric line shape of a Fano resonance. The unique feature of these Fano resonances is that they allow to continuously tune the key parameter — the coupling strength Γ between the discrete state and the degenerate continuum — by varying the bias voltage. Using this feature, we directly show that the Fano coupling leads to a fast polarization decay. We also investigate the dependence of the Fano parameters on the structure of the superlattice and compare to an extensive theoretical model of the resonances. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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