Publications [#150562] of Adrienne D. Stiff-Roberts

Papers Published

1. S. Chakrabarti and A. D. Stiff-roberts and X. H. Su and P. Bhattacharya and G. Ariyawansa and A. G. U. Perera, High-performance mid-infrared quantum dot infrared photodetectors, Journal Of Physics D-applied Physics, vol. 38 no. 13 (July, 2005), pp. 2135 -- 2141, ISSN 0022-3727
   (last updated on 2008/10/16)

   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 (10(11) 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.