Publications [#66834] of Adrienne D. Stiff-Roberts

Papers Published

1. Chakrabarti, S. and Stiff-Roberts, A.D. and Su, X.H. and Bhattacharya, P. and Ariyawansa, G. and Perera, A.G.U., High-performance mid-infrared quantum dot infrared photodetectors, Journal of Physics D: Applied Physics, vol. 38 no. 13 (2005), pp. 2135 - 2141 [009]
   (last updated on 2007/04/16)

   Abstract:
   Quantum dot infrared photodetectors (QDIPs) have emerged as attractive devices for sensing long wavelength radiation. Their principle of operation is based on intersublevel transitions in quantum dots (QDs). Three-dimensional quantum confinement offers the advantages of normal incidence operation, low dark currents and high-temperature operation. The performance characteristics of mid-infrared devices with three kinds of novel heterostructures in the active region are described here. These are a device with upto 70 QD layers, a device with a superlattice in the active region, and a tunnel QDIP. Low dark currents (1.59 A cm^-2 at 300 K), large responsivity (2.5 A W ^-1 at 78 K) and large specific detectivity (10¹¹ cm Hz^1/2 W^-1 at 100 K) are measured in these devices. It is evident that QDIPs will find application in the design of high-temperature focal plane arrays. Imaging with small QD detector arrays using the raster scanning technique is also demonstrated. © 2005 IOP Publishing Ltd.

   Keywords:
   Semiconductor quantum dots;Heterojunctions;High temperature effects;Photocurrents;Quantum efficiency;Superlattices;Phonons;