Quantum Transport In Chern Insulator

Haldane model has been extensively studied as a simple model of quantum anomalous Hall Effect.Some exotic physics emerge especially in several kinds of novel geometry.The Haldane model was previously explained as a Chern insulator with energy band structure,Chern number,density of states and some local parameters,but a few work was devoted to quantum transport of Chern insulator and the model was rarely used to design topological quantum device for harsh experimental conditions.In this paper,we construct a large system based on Haldane model to compute the properties of quantum transport.We theoretically proposed a method for manipulating the topological quantum device.We firstly construct a Haldane model with 576 sites in a ring geometry with 6-fold rotational symmetry.The high Chern number(C=2)is introduced in quantum transport to interpret the electronic state.The result indicates that the value of conductance platform equals to the Chern number and parameter of quantum transport can supplementally explain the topological state compared with traditional research methods.We additionally investigate the transport properties of Chern insulator in Quasicrystal and the conductance has a more detailed physical picture than local Chern number.Then we enlarge the system to 18182 sites to meet actual size of quantum device.The energy band structure,local Chern number and some traditional parameters are difficult to be computed out in the large system but the quantum transport parameters,like local current and conductance,can be derived easily.In order to manipulate the transport properties of quantum devices,we add the Aharonov-Bohm effect into the center of the ring to tune the conductance and the periodically variable conductance appeared.Finally,the disordered onsite energy is introduced to test the stability of the system.The topological state can keep stable when the level of disorder intensity is less than 2.