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Pseudospin ferromagnetism in double-quantum-wire systems

D. -W. Wang·E. G. Mishchenko·E. Demler
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Abstract

We propose that a pseudospin ferromagnetic (i.e inter-wire coherent) state can exist in a system of two parallel wires of finite width in the presence of a perpendicular magnetic field. This novel quantum many-body state appears when the inter wire distance decreases below a certain critical value which depends on the magnetic field. We determine the phase boundary of the ferromagnetic phase by analyzing the softening of the spin-mode velocity using the bosonization approach. We also discuss signatures of this state in tunneling and Coulomb drag experiments.

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D. -W. Wang, E. G. Mishchenko, E. Demler. 2005-10-04. Pseudospin ferromagnetism in double-quantum-wire systems. https://doi.org/10.1103/physrevlett.95.086802

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