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Allen P Mills

Publications and source records attributed to Allen P Mills.

3 recordsLinked to original sources

Weak-localization-like temperature-dependent conductivity of a dilute two-dimensional hole gas in a parallel magnetic field.

We have studied the magnetotransport properties of a high mobility two-dimensional hole gas (2DHG) in a 10 nm GaAs quantum well with densities in the range of (0.7-1.6) x 10(10) cm(-2) on the metallic side of the zero-field "metal-insulator transition." In a parallel field well above B(c) that suppresses the metallic conductivity, the 2DHG exhibits a conductivity Delta(g)(T) approximately (1/pi) (e(2)/h)lnT reminiscent of weak localization for Fermi liquids. The experiments are consistent with the coexistence of two phases in our system: a metallic phase and a weakly insulating Fermi liquid phase.

Journal Article↗

Two-dimensional metal in a parallel magnetic field.

We have investigated the effect of an in-plane parallel magnetic field (B(axially) on two high mobility metallic-like dilute two-dimensional hole gas systems in GaAs quantum wells. The experiments reveal that, while suppressing the magnitude of the low temperature resistance drop, B(axially) does not affect E(a), the characteristic energy scale of the metallic resistance drop. The field B(c) at which the metallic-like resistance drop vanishes is dependent on both the width of the quantum well and the orientation of B(axially). It is unexpected that E(a) is unaffected by B(axially) up to B(c) despite the fact that the Zeeman energy at B(c) is roughly equal to E(a).

Journal Article↗

Gene expression profiling diagnosis through DNA molecular computation.

Gene expression profiling is the characterization of cells based on the level of gene activity represented by concentrations of complementary DNA reverse transcribed from messenger RNA. The spectrum of cDNA concentrations, the expression profile, is determined using a DNA microarray. Although this approach is valuable for research, a simpler scheme that would give answers on a shorter time-scale for clinical applications is needed. An Adleman DNA self-assembly computer that would use cDNA as input might be ideal for clinical cell discrimination and a neural network architecture would be appropriate for making the necessary classifications. Preliminary experimental results suggest that expression profiling should be feasible using a DNA neural network that acts directly on cDNA.

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