Quantum spin pumping at fractionally quantized magnetization state for a system with competing exchange interactions

Quantum Pump for Fractional Charge

We propose a theoretical scenario for pumping of fractionally charged quasi-particle in the context of $ν=1/3$ fractional quantum Hall liquid. We consider quasi-particle pumping across an anti-dot level tuned close to the resonance. Fractional charge pumping is achieved by slow and periodic modulation of coupling of the anti-dot level to left and right moving edges of a Hall bar set-up. This is attained by periodically modulating the gate voltages controlling the couplings. In order to obtain quantization of pumped charge in the unit of the electronic charge fraction ($νe$) per pumping cycle i…

Theory of Competing Charge Density Wave, Kekule and Antiferromagnetic ordered Fractional Quantum Hall states in Graphene aligned with Boron Nitride

We investigate spin and valley symmetry-broken fractional quantum Hall phases within a formalism that naturally extends the paradigm of quantum Hall ferromagnetism from integer to fractional quantum Hall states, allowing us to construct detailed phase diagrams for a large class of multi-component states. Motivated by recent experiments on Graphene aligned with a Boron Nitride substrate, we predict a sequence of transitions realized by increasing the magnetic field, starting from a sub-lattice polarized state to a valley coherent Kekule charge density wave state and further to an anti-ferromagn…

Fractional charge pumping of interacting bosons in one-dimensional superlattice

Motivated by experimental realizations of integer quantized charge pumping in one-dimensional superlattices~[Nat. Phys. 12, 350 (2016); Nat. Phys. 12, 296 (2016)], we generalize and propose the adiabatic pumping of a fractionalized charge in interacting bosonic systems. This is achieved by dynamically sweeping the modulated potential in a class of one-dimensional interacting systems. As concrete examples, we show the charge pumping of interacting bosons at certain fractionally occupied fillings. We find that, for a given ground state, the charge pumping in a complete potential cycle is quantiz…

1/9 磁化平台：具有竞争性更远邻相互作用的经典 Kagome 伊辛铁磁体

1/9 Magnetization Plateau in a Classical Kagome Ising Ferromagnet with Competing Further-Neighbor Interactions

通过模拟退火蒙特卡洛方法，研究具有铁磁最近邻和反铁磁次近邻及第三近邻耦合的经典 Kagome 伊辛模型，发现第三近邻相互作用导致 1/9 磁化平台和 3×3 磁超胞的新型有序相，其临界温度几乎独立于耦合强度。