Magic-angle effects in the interlayer magnetoresistance of quasi-one-dimensional metals due to interchain incoherence

Abstract

The dependence of the magnetoresistance of quasi-one-dimensional metals on the direction of the magnetic field show dips when the field is tilted at the so-called magic angles determined by the structural dimensions of the materials. There is currently no accepted explanation for these magic-angle effects. We present a possible explanation. Our model is based on the assumption that, the intralayer transport in the second most conducting direction has a small contribution from incoherent electrons. This incoherence is modeled by a small uncertainty in momentum perpendicular to the most conducting (chain) direction. Our model predicts the magic angles seen in interlayer transport measurements for different orientations of the field. We compare our results to predictions by other models and to experiment.

Numerical investigation of Nernst effect in quasi-one-dimensional systems

“…This picture is confirmed by either semiclassical transport theory or ͑in͒coherent interplane single particle tunneling. 15,[17][18][19] A recent 4 rotation study of the conductivity of ͑TMTSF͒ 2 PF 6 by Kang et al 26 provides experimental support to this idea. However, none of these studies addresses whether the giant Nernst resonances found at magic angles can also be explained by introducing a finite magnetic field along the a axis.…”

“…In reciprocal space, a field along the magic angles induces electron motion along commensurate k space orbits. 8 Despite many theoretical efforts to describe the magic angle effects, [7][8][9][10][11][12][13][14][15][16][17][18][19][20] there is as yet no satisfactory explanation. Recently, the second manifestations of the magic angle effects, giant Nernst resonances, were discovered in ͑TMTSF͒ 2 PF 6 under pressure.…”

Polarization dependent asymmetric magneto-resistance features in nanocrystalline diamond films

“…Angle-dependent MR (AMR) features with oscillations are observed in layered structures having extremely low degree of disorder, such as in specific organic superconductors, metals, graphene, and artificial superlattice structures (SL). [1][2][3][4][5] An effective disordered SL description of ultrananocrystalline diamond (UNCD) films consists of sp 2 bonded carbon layers in the grain boundary regions (GB) separated by diamond grains has been claimed based on the micro-structural study as well as electronic transport in these films. 6 Nitrogen incorporated UNCD films have demonstrated superb electrical transport [6][7][8][9][10][11] including 3D anisotropic weak localization (WL) beyond hopping transport.…”

Magic Angle Effects of One-Dimensional Axis Conductivity in Quasi-One-Dimensional Conductors

“…Experimentally, dips, instead of peaks, of the resistance at the magic angles are observed in both R xx and R zz in various quasi-one-dimensional organic conductors, (TMTSF) Other angle dependences of the magnoresistance have also been observed in quasi-two-dimensional conductors [12,13,14], and in quasi-one-dimensional conductors with rotating magnetic field in the a-c plane [15] and in the a-b plane [16]. These angle dependences are explained in the semiclassical theory [15,16,17,18] and they are used as powerful tools to observe the shape of the Fermi surface in low-dimensional systems.For MAE, however, no complete explanation has been given yet, although there exit several theories [19,20,21,22,23,24,25,26,27,28]. Interesting idea of the magnetic-field-induced confinement [22] has been proposed to explain MAE.…”

“…For MAE, however, no complete explanation has been given yet, although there exit several theories [19,20,21,22,23,24,25,26,27,28]. Interesting idea of the magnetic-field-induced confinement [22] has been proposed to explain MAE.…”