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Field-induced spin-density-wave phases in TMTSF organic conductors: quantization versus non-quantization

K. Sengupta·N. Dupuis
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Abstract

We study the magnetic-field-induced spin-density-wave (FISDW) phases in TMTSF organic conductors in the framework of the quantized nesting model. In agreement with recent suggestions, we find that the SDW wave-vector ${\bf Q}$ deviates from its quantized value near the transition temperature $T_c$ for all phases with quantum numbers $N>0$. Deviations from quantization are more pronounced at low pressure and higher $N$ and may lead to a suppression of the first-order transitions $N+1\to N$ for $N\ge 5$. Below a critical pressure, we find that the N=0 phase invades the entire phase diagram in accordance with earlier experiments. We also show that at T=0, the quantization of ${\bf Q}$ and hence the Hall conductance is always exact. Our results suggest a novel phase transition/crossover at intermediate temperatures between phases with quantized and non-quantized ${\bf Q}$.

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K. Sengupta, N. Dupuis. 2003-02-07. Field-induced spin-density-wave phases in TMTSF organic conductors: quantization versus non-quantization. https://doi.org/10.1103/physrevb.68.094431

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