N. E. Lumpkin

QUANTIZED CONDUCTANCE IN QUANTUM WIRES WITH GATE-CONTROLLED WIDTH AND ELECTRON DENSITY

We describe quantum wires and point contacts fabricated in GaAs/AlxGa1−xAs heterostructures that are free of the disorder introduced by modulation doping and in which the electron density and the confining potential are separately adjustable by lithographically defined gates. We observe conductance plateaus quantized near even multiples of e2/h in 2 μm wires and up to 15 conductance steps in 5 μm wires at temperatures below 1 K. Near the conductance threshold the quantum point contact and the 2 μm wire both show additional structure below 2e2/h.

Many-body spin-related phenomena in ultra low-disorder quantum wires

Zero length quantum wires (or point contacts) exhibit unexplained conductance structure close to

A self-aligned fabrication process for silicon quantum computer devices

0.7\ifmmode\times\else\texttimes\fi{}{2e}^{2}/h

Experimental determination of theB−Tphase diagram ofYBa2Cu3O7−δto 150 T forB⊥c

in the absence of an applied magnetic field. We have studied the density- and temperature-dependent conductance of ultra low-disorder

Nanofabrication processes for single-ion implantation of silicon quantum computer devices

\mathrm{GaAs}/{\mathrm{Al}}_{x}{\mathrm{Ga}}_{1\ensuremath{-}x}\mathrm{As}

Quantization and chiral edge state properties in nearly 3D quantum well structures

quantum wires with nominal lengths

Cyclotron resonance in undoped, top-gated heterostructures

l=0,

Quantum point contact in a magnetic field: Far-infrared resonant heating observed in photoconductivity

0.5, and 2

INVESTIGATION OF LOW- AND HIGH-RESISTANCE NI-GE-AU OHMIC CONTACTS TO N+ GAAS USING ELECTRON MICROBEAM AND SURFACE ANALYTICAL TECHNIQUES

\ensuremath{\mu}\mathrm{m},

Magnetic susceptibility of the normal-superconducting transition in high-purity single-crystal α -uranium

fabricated from structures free of the disorder associated with modulation doping. In a direct comparison in zero magnetic field we observe structure near