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arXiv · 0707.0153

Anomalous giant piezoresistance in AlAs 2D electrons with anti-dot lattices

O. Gunawan·T. Gokmen·Y. P. Shkolnikov·E. P. De Poortere·M. Shayegan
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Abstract

An AlAs two-dimensional electron system patterned with an anti-dot lattice exhibits a giant piezoresistance (GPR) effect, with a sign opposite to the piezoresistance observed in the unpatterned region. We trace the origin of this anomalous GPR to the non-uniform strain in the anti-dot lattice and the exclusion of electrons occupying the two conduction band valleys from different regions of the sample. This is analogous to the well-known giant magnetoresistance (GMR) effect, with valley playing the role of spin and strain the role of magnetic field.

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O. Gunawan, T. Gokmen, Y. P. Shkolnikov, E. P. De Poortere, M. Shayegan. 2007-07-02. Anomalous giant piezoresistance in AlAs 2D electrons with anti-dot lattices. https://doi.org/10.1103/physrevlett.100.036602

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