Liu Zhao, Balram Ajit C, Papić Zlatko, Gromov Andrey
Zhejiang Institute of Modern Physics, Zhejiang University, Hangzhou 310027, China.
Institute of Mathematical Sciences, HBNI, CIT Campus, Chennai 600113, India.
Phys Rev Lett. 2021 Feb 19;126(7):076604. doi: 10.1103/PhysRevLett.126.076604.
We introduce different types of quenches to probe the nonequilibrium dynamics and multiple collective modes of bilayer fractional quantum Hall states. We show that applying an electric field in one layer induces oscillations of a spin-1 degree of freedom, whose frequency matches the long-wavelength limit of the dipole mode. On the other hand, oscillations of the long-wavelength limit of the quadrupole mode, i.e., the spin-2 graviton, as well as the combination of two spin-1 states, can be activated by a sudden change of band mass anisotropy. We construct an effective field theory to describe the quench dynamics of these collective modes. In particular, we derive the dynamics for both the spin-2 and the spin-1 states and demonstrate their excellent agreement with numerics.
我们引入不同类型的猝灭来探究双层分数量子霍尔态的非平衡动力学和多种集体模式。我们表明，在一层中施加电场会诱发自旋为1的自由度的振荡，其频率与偶极模式的长波长极限相匹配。另一方面，四极模式的长波长极限（即自旋为2的引力子）的振荡以及两个自旋为1态的组合，可以通过能带质量各向异性的突然变化来激活。我们构建了一个有效场论来描述这些集体模式的猝灭动力学。特别地，我们推导了自旋为2和自旋为1态的动力学，并证明它们与数值计算结果高度吻合。
