Near-Band Edge Spectral Hole in Quantum Well: No Evidence for Subpicosecond Plasma Thermalization |
| M. Mos̆ko and A. Mos̆ková Institute of Electrical Engineering, Slovak Academy of Sciences, Dúbravská cesta 9, 842 39 Bratislava, Slovak Republic |
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| We show that at low carrier energies and densities the carriers in a two-dimensional Coulomb gas interact via classical unscreened carrier-carrier collisions. This allows us to calculate exactly the thermalization due to the two-dimensional carrier-carrier collisions in a nonthermal low-density (≈1010 cm-2) two-dimensional plasma excited near the band edge of an undoped GaAs quantum well. The thermalization is found to be 10-15 times slower than the 200 fs thermalization deduced from the previous spectral-hole burning measurements, which means that the spectral hole does not reflect the thermalization process. We also show that the Born approximation fails in describing such carrier-carrier collisions. |
| DOI: 10.12693/APhysPolA.90.1055 PACS numbers: 73.50.-h, 73.50.Bk, 78.47.+p |