0846834_Khodaparast

1. CAREER: Integrated Research and Education to Probe Coherent and Quantum States in the Presence of Strong Spin-Orbit CouplingGiti A. Khodaparast, Virginia Polytechnic Institute and State University, DMR 0846834 Fig. 1: Two-color normalized differential transmission at 77 K for InMnAs and InMnsb, with the pump and probe laser pulses tuned at 800 nm and 3.467 mm, respectively. A two level relaxation dynamic, where both the intervalley and intravalley relaxations can contribute to the initial relaxations (circled in the figure), has been observed. (Samples are provided by Wessels’ group, Northwestern University.) Fig. 2: Possible optical transitions in InMnAs with 800 nm pulses for several interband transition from light and heavy holes for the calculated bands of In 0.96Mn 0.04As at 290 K for Tc = 330 K. The energy bands are spin-split due to the ferromagnetism of the Mn dopants. The electrons can be scattered back and forth between the  and L valleys. (Theory developed in Stanton’s Group in Univ. of Florida) Physical Review B, 85, 125313 (2012).

2. CAREER: Integrated Research and Education to Probe Coherent and Quantum States in the Presence of Strong Spin-Orbit CouplingGiti A. Khodaparast, Virginia Polytechnic Institute and State University, DMR 0846834 In summer of 2012, I supervised three undergraduate students Amnah Eltahir, Doug Wilson, and Jameel McMillan, supported by REU supplements. My educational activities have been engaging students from underrepresented groups. Amnah and Doug are working on magneto-transport measurements using a closed cycled cryostat and electromagnet.