论文标题
随机磁场和Dirac Fermi表面
Random Magnetic Field and the Dirac Fermi Surface
论文作者
论文摘要
我们在有限密度下研究单个2D Dirac Fermion，受到淬灭的随机磁场的影响。在低能量和足够弱的障碍下，该理论映射到无限的一维手性费米子（与费米表面上的每个点相关），并由随机矢量电位结合。这种低能的理论表现出可解决的随机固定线，我们在其中直接计算了各种无序的可观察物，而无需通常的复制品，超对称性或Keldysh技术。我们在无碰撞的$ \ hbarω/k_b t \ rightarrow \ infty $限制中找到纵向直流电导率，是非额外的，并且沿固定线路不断变化。
We study a single 2d Dirac fermion at finite density, subject to a quenched random magnetic field. At low energies and sufficiently weak disorder, the theory maps onto an infinite collection of 1d chiral fermions (associated to each point on the Fermi surface) coupled by a random vector potential. This low-energy theory exhibits an exactly solvable random fixed line, along which we directly compute various disorder-averaged observables without the need for the usual replica, supersymmetry, or Keldysh techniques. We find the longitudinal dc conductivity in the collisionless $\hbar ω/k_B T \rightarrow \infty$ limit to be nonuniversal and to vary continuously along the fixed line.
