276 research outputs found
On the Origin of the Anomalous Upper Critical Field in Quasi-One-Dimensional Superconductors
Upper critical field, H_c2, in quasi-1D superconductors is investigated by
the weak coupling renormalization group technique. It is shown that H_c2
greatly exceeds not only the Pauli limit, but also the conventional
paramagnetic limit of the Flude-Ferrell-Larkin-Ovchinnikov (FFLO) state. This
increase is mainly due to quasi-1D fluctuations effect as triggered by
interference between unconventional superconductivity and density-wave
instabilities. Our results give a novel viewpoint on the large H_c2 observed in
TMTSF-salts in terms of a d-wave FFLO state that is predicted to be verified by
the H_c2 measurements under pressure.Comment: 5 pages, 4 figure
HOIL-1LユビキチンリガーゼはLUBACをモノユビキチン化することで免疫応答と細胞死を制御する
京都大学0048新制・課程博士博士(医学)甲第22738号医博第4656号新制||医||1046(附属図書館)京都大学大学院医学研究科医学専攻(主査)教授 竹内 理, 教授 中川 一路, 教授 生田 宏一学位規則第4条第1項該当Doctor of Medical ScienceKyoto UniversityDFA
Angle dependence of the orbital magnetoresistance in bismuth
We present an extensive study of angle-dependent transverse magnetoresistance
in bismuth, with a magnetic field perpendicular to the applied electric current
and rotating in three distinct crystallographic planes. The observed angular
oscillations are confronted with the expectations of semi-classic transport
theory for a multi-valley system with anisotropic mobility and the agreement
allows us to quantify the components of the mobility tensor for both electrons
and holes. A quadratic temperature dependence is resolved. As Hartman argued
long ago, this indicates that inelastic resistivity in bismuth is dominated by
carrier-carrier scattering. At low temperature and high magnetic field, the
threefold symmetry of the lattice is suddenly lost. Specifically, a
rotation of magnetic field around the trigonal axis modifies the amplitude of
the magneto-resistance below a field-dependent temperature. By following the
evolution of this anomaly as a function of temperature and magnetic field, we
mapped the boundary in the (field, temperature) plane separating two electronic
states. In the less-symmetric state, confined to low temperature and high
magnetic field, the three Dirac valleys cease to be rotationally invariant. We
discuss the possible origins of this spontaneous valley polarization, including
a valley-nematic scenario.Comment: 15 pages, 14 figure
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