|Title||High-performance mid-infrared quantum dot infrared photodetectors|
|Publication Type||Journal Article|
|Year of Publication||2005|
|Authors||S Chakrabarti, AD Stiff-Roberts, XH Su, P Bhattacharya, G Ariyawansa, and AGU Perera|
|Journal||Journal of Physics D: Applied Physics|
|Pagination||2135 - 2141|
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 Hz1/2 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.
|Short Title||Journal of Physics D: Applied Physics|