Hot electron energy and momentum relaxation in GaAs/AlAs and GaAs/Ga1-xAlxAs multiple quantum wells

✍ Scribed by E. Oztürk; A. Straw; N. Balkan

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 195 KB
• Volume: 15
• Category: Article
• ISSN: 0749-6036
• DOI: 10.1006/spmi.1994.1033

✦ Synopsis

Experimental results on high electric field longitudinal transport in GaAs/AlAs and (G a A s / G a_{1-x} A l_{x} A s) multiple quantum wells (MQW) are presented and compared with the prediction of a dielectric continuum model. We draw from our experiments the following four conclusions.

(i) In (\operatorname{GaAs} / \mathrm{Ca}{1-x} A l{x} A s) systems the dominant energy and momentum relaxation mechanism is through scattering with GaA.s-modes.

(ii) However, in GaAs/AlAs systems the AlAs interface mode is dominant in relaxing the energy and momentum of the quantum well electrons.

(iii) The hot electron momentum relaxation as obtained from the high-field drift velocity experiments is strongly affected by the production of hot phonons as expected from a model involving a non-drifting hot phonon distribution.

(iv) The importance of the AlAs interface mode in (G a A s / G a_{I-x} A l_{x} A s \mathrm{MQW}) is not the result of the intrinsic scattering rate but related to its shorter lifetime, compared to GaAs modes.