Magnetic field influence on the low and high electric field transport in the spin-density wave state of the organic conductor (TMTSF)2NO3

A field description of spin-density-wave (SDW) in a quasi-two-dimensional metal with open Fermi surface in magnetic field, is proposed. The SDW transition temperature, T c (H), and the Hall conductivity σxy, are calculated. The dependence T c (H) is found to be different from that of the Bardeen-Cooper-Schrieffer model, in particular, a threshold field, H c , found its natural explanation. It is proved that the quantized Hall conductivity arises from the chiral anomaly terms in the effective action provided there is pinning of chemical potential in the gap of extended states.

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High magnetic field NMR investigation of the spin density wave phase of TMTSF2PF6

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:20020445 ◽

2002 ◽

Vol 12 (9) ◽

pp. 389-389

Author(s):

W. G. Clark ◽

F. Zamborsky ◽

B. Alavi ◽

P. Vonlanthen ◽

W. Moulton ◽

...

Keyword(s):

Magnetic Field ◽

Spin Density ◽

Density Wave ◽

Spin Density Wave ◽

Proton Relaxation ◽

High Magnetic Fields ◽

Organic Conductor ◽

First Order ◽

The Magnetic Field ◽

Very High

We report proton NMR measurements of the effect of very high magnetic fields up to 44.7 T (1.9 GHz) on the spin density wave (SDW) transition of the organic conductor TMTSF2PF6. Up to 1.8 GHz, no effect of critical slowing close to the transition is seen on the proton relaxation rate (1/T1), which is determined by the SDW fluctuations associated with the phase transition at the NMR frequency. Thus, the correlation time for such fluctuations is less than $1O^{-10}$s. A possible explanation for the absence of longer correlation times is that the transition is weakly first order, so that the full critical divergence is never achieved. The measurements also show a dependence of the transition temperature on the orientation of the magnetic field and a quadratic dependence on its magnitude that agrees with earlier transport measurements at lower fields. The UCLA part of this work was supported by NSF Grant DMR-0072524.

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Magnetic Evidence for Reentrant Field-Induced Spin Density Waves

MRS Proceedings ◽

10.1557/proc-173-227 ◽

1989 ◽

Vol 173 ◽

Cited By ~ 1

Author(s):

M. J. Naughton ◽

R. V. Chamberlin ◽

X. Yan ◽

P. M. Chaikin ◽

L. Y. Chiang

Keyword(s):

Magnetic Field ◽

Spin Density ◽

High Field ◽

Density Wave ◽

Spin Density Wave ◽

Metallic Phase ◽

Wave State ◽

T Phase ◽

Resistance Data ◽

The Magnetic Field

ABSTRACTHigh magnetic field (to 31T) d.c. magnetization measurements on the quasi-one dimensional organic conductor (TMTSF) 2ClO4 yield thermodynamic evidence for the reentrance of a metallic phase from the magnetic field-induced spin density wave state. The H-T phase diagram developed previously from magnetotransport measurements is reproduced from 8 to 26 tesla. The reentrance occurs as a sharp collapse of M(H) to (near) zero magnetization in the high field metal phase. For fields above 27 tesla, deHaas-van Alphen-like oscillations appear, similar to earlier resistance data, as well as other features possibly signifying multiple transitions in the very high field regime.

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