Solid state communications vol:110 issue:3 pages:169-171
We performed magneto-resistance measurements on a semi-metallic InAs-GaSb quantum well. By shining visible light on the sample, a Negative Persistent Photoconductivity effect (NPPC) was observed. Overnight illumination reduced the electron density of the sample from 9.54 x 10(11) cm(-2) to 9.04 x 10(11) cm(-2). A possible explanation for this effect is being sought in interface defect states. (C) 1999 Elsevier Science Ltd. All rights reserved.