On Mon, Nov 1, 2010 at 1:57 PM, Joey Sulpizio <jopizio@stanford.edu> wrote:
> DEPT OF PHYSICS
>
> DISSERTATION DEFENSE
>
> Ph.D. Candidate: Joseph A. Sulpizio
>
> Research Advisor: David Goldhaber-Gordon
>
> Date: Wednesday, November 3, 2010
> Time: 9AM
> Location: McCullough 335
>
> Title: Ballistic Transport in Quantum Hole Wires
>
> Abstract: Recent experiments on ballistic electron transport in
> semiconductor nanowires have revealed a rich set of phenomena
> associated with one-dimensional (1D) quantum systems. In this thesis,
> we present measurements of hole transport in ballistic quantum wires
> fabricated by GaAs/AlGaAs cleaved-edge overgrowth (CEO), as hole
> transport in GaAs is expected to exhibit enhanced effects of
> electron-electron interactions and spin-orbit coupling as compared
> with transport of electrons. To interpret these results, we have
> developed a new, broadly-applicable approach to analyzing the
> transport measurements of a ballistic 1D quantum system. We validate
> our analysis approach using nonlinear conductance data of both
> electron and hole CEO quantum wires, where we find evidence for the
> importance of charge interactions. Applying our analysis to
> measurements of hole transport in magnetic field, we find strong
> g-factor anisotropy, which we associate with spin-orbit coupling.
> Finally, we present the first observation of a predicted "spin-orbit
> gap" in the 1D density of states, where counter-propagating spins are
> accompanied by a clear signal in the conductance.
>
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