Technical Overview. In this project, the carrier lifetimes and scattering mechanisms in self assembled quantum dots are being investigated using femtosecond pump-probe spectroscopy. The InAs/InGaAs quantum dots in a well system provides a unique system, in which photogenerated carriers are initially unconfined, but later relax to a two dimensional quantum well and finally to a quasi zero dimesional quantum dot. We have recently purchased a femtosecond laser system, which is being used for the pump-probe measurements. We are presently undertaking studies on self-assembled quantum dots and will start investigating the other material systems in the near future.

This work is funded by the Department of Energy Basic Energy Sciences and by the Army Research Office.

Collaborators in this work are Dr. Huffaker (ECE, UNM), Dr. Toni Taylor (LANL) Dr. Lobad and Dr. Schlie (AFRL).

Selected Publications.
“Time-resolved mid-infrared dynamics of an InAs/InGaAs quantum-dots-in-a-well detector”, R. P. Prasankumar, R. D. Averitt, A. J. Taylor (LANL), G. von Winckel, A. Stintz and S. Krishna (UNM), CLEO 2004.

“Ultrafast Relaxation in Nanostructured Materials IEEE Laser/Electro-optics," R. P. Prasankumar, R. D. Averitt, A. J. Taylor, N.W. Bernstein, P. Rotella, G. von Winckel, A. Stintz and S. Krishna, (INVITED) Annual Meeting, Sydney Australia, November 2005.

 

Updated 2/14/06

Carrier Dynamics
InAs/InGaAs Quantum Dots in a Quantum Well