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arXiv · 1007.4251

Insulating phases of electrons on a zigzag strip in the orbital magnetic field

Hsin-Hua Lai·Olexei I. Motrunich
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Abstract

We consider electrons on a two-leg triangular ladder at half-filling and in an orbital magnetic field. In a two-band regime in the absence of the field, the electronic system remains conducting for weak interactions since there is no four-fermion Umklapp term. We find that in the presence of the orbital field there is a four-fermion Umklapp and it is always relevant for repulsive interactions. Thus in this special ladder, the combination of the orbital magnetic field and interactions provides a mechanism to drive metal-insulator transition already at weak coupling. We discuss properties of the possible resulting phases C0S2 and various C0S1 and C0S0.

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Hsin-Hua Lai, Olexei I. Motrunich. 2010-11-17. Insulating phases of electrons on a zigzag strip in the orbital magnetic field. https://doi.org/10.1103/physrevb.82.195119

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