Abstract:

The field of semiconductor spintronics has undergone explosive growth over the past few years due to the promise of applications in areas such as semiconductor logic and memory.  For example, the incorporation of ferromagnetic materials into traditional transistors may lead to nonvolatile reprogrammable logic devices, and low power spin-based switching is predicted to dramatically enhance device scalability.[1]  In addition to incoherent spin devices, which rely on control of a net spin population for enhanced functionality, one may also envision devices that rely on spin coherence, in which coherent operations and controllable entanglement are the basis for quantum logic.[2]  Our research group is using ultrafast optical techniques to explore spin dynamics and spin control in a variety of semiconductor materials of interest for applications in spintronics and quantum information.  Our recent results in the area of ultrafast control of ferromagnetic order in GaMnAs and in the study of electron spin dynamics in InAs quantum dots will be highlighted.  This work supported by CFI, NSERC, DARPA and NSF.

[1]   S. Datta and B. Das, Appl. Phys. Lett. 56, 665 (1990); M. E. Flatte and G. Vignale, Appl. Phys. Lett. 78, 1273 (2001); M. E. Flatte et al., Appl. Phys. Lett. 82 4740 (2003); K. C. Hall et al., Appl. Phys. Lett. 83, 2937 (2003); K. C. Hall et al. Appl. Phys. Lett. 88, 162503 (2006).

[2]    D. Loss and D. P. DiVincenzo, Phys. Rev. A 57,120 (1998); P. Chen, C. Piermarocchi, and L. J. Sham, Phys. Rev. Lett. 87, 067401 (2001).