Professor Jacob Khurgin, Johns Hopkins University

"Interesting Phenomena due to band mixing in Zinc Blende bulk and QW materials"

Wednesday 28th September 2005: University of Glasgow

4 pm, Room 408 of the Rankine Building (Electrical Engineering)


Abstract

In this talk I will describe theory of three remarkable, and, to the best of my knowledge, unknown phenomena associated with the peculiarities of band structure of zinc blende semiconductors.

First phenomenon is the photo-generating directional ballistic carriers in zinc blende QW’s using elliptically polarized light. I will show that large ballistic currents can be generated and coherently controlled by controlling wavelength and polarization state of above-the-gap excitation. Practical implications for THz generation will be considered.

Second phenomenon is ability to achieve high degree of spin polarization using intersubband transitions in doped quantum wells. Potential implications for the elusive spintronics field will be discussed.

The third part of my talk will deal with a more fundamental issue of defining permanent dipole moment of Bloch states in zinc blende lattice. I will demonstrate how simple (yet rigorous) introduction of permanent dipole greatly facilitates understanding and estimating nonlinear susceptibilities for sum and frequency generation, electro-optic, Raman, and elasto-optic coefficients.


Page last updated by Graham Turnbull:  10 August 2005