 |
 |
 |
Publication # 083 |
|
| I. Bar-Joseph, J. M. Kuo, C. Klingshirn, G. Livescu,
D. A. B. Miller, T. Y. Chang and D. S. Chemla, "Absorption
Spectroscopy of the Continuous Transition from Low to High Electron Density in a Single
Modulation Doped InGaAs Quantum Well" Phys. Rev. Lett. 59, 1357-1360, (1987). The authors perform differential absorption spectroscopy of a single modulation-doped InGaAs quantum well as its electron density is varied continuously from full (N approximately=8*10/sup 11/ cm/sup -2/) to empty (N approximately=0) by a gate electrode, allowing direct measurement of the density-dependent changes of transition energies and strengths. They observe a progressive quenching of the optical transition at the first subband and red shifts and broadening at higher subbands. They show that the dominant mechanisms are phase-space filling and the quantum-confined Stark effect. This technique also allows direct in situ measurements of the density and temperature of the 2D electron gas in such field-effect-transistor structures |
|
Full text available for
download