Phase coherence and the Nernst effect at magic angles in organic conductors

N. P. Ong; Weida Wu; P. M. Chaikin; P. W. Anderson

doi:10.1209/epl/i2004-10017-9

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Phase coherence and the Nernst effect at magic angles in organic conductors

N. P. Ong·Weida Wu·P. M. Chaikin·P. W. Anderson

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Abstract

A giant Nernst signal was recently observed for fields near crystallographic directions in (TMTSF)$_2$PF$_6$. Such large Nernst signals are most naturally associated with the motion of pancake vortices. We propose a model in which phase coherence is destroyed throughout the sample except in planes closely aligned with the applied field $\bf H$. A small tilt above or below the plane changes the direction and density of the penetrating vortices and leads to a Nernst signal that varies with the tilt angle of $\bf H$ as observed. The resistance notches at magic angles are understood in terms of flux-flow dissipation from field-induced vortices.

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N. P. Ong, Weida Wu, P. M. Chaikin, P. W. Anderson. 2004-01-09. Phase coherence and the Nernst effect at magic angles in organic conductors. https://doi.org/10.1209/epl%2Fi2004-10017-9

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