Thermal Transport Properties Of Majorana Quantum Composite Structure

Majorana fermion was introduced by Ettore Majorana.Different from ordinary fermions,Majorana fermions are their own antiparticles,and two spatially separated Majorana bound states(MBSs)define a nonlocal fermionic state.They have attracted great attention due to both their fundamental interests and potential applications for the decoherence-free quantum computation in condensed matter physics.Besides,they also have potential application in high efficient thermal electrical energy conversion.Hence,there are more and more researches about Majorana fermion around the world.This paper works on the thermal transport properties of Majorana composite structure.In the first work,we calculate the current noise cross correlation and the differential conductance in the Majorana bound states(MBSs)comb.The Seebeck coefficient and the thermal electrical figure of merit are calculated for different temperature and dives size in the QAH-TSC-QAH structure in the second work.For the first work,we find that the MBSs comb can be effectively modulated by the up-part quantum dots due to the effective resonance between the Majorana bound state and the dot.For only one“QD-MBSs-QD”building block,N=1,the current noise cross correlation is negative at small bias and increases to positive value at lager bias.A zero bias conductance peak of 2e~2/h can be found.Next,for N?2,the current noise cross correlation is zero at small bias and increases to positive value at larger bias.Different from the case of N=1,the zero bias conductance peak is 4 e~2/h due to the sole contribution from local Andreev reflection.Besides,we find that the differential conductance is robust against the influence of N.For the second work,due to the influence of chiral Majorana edge modes the Seebeck coefficient and the thermal electrical figure of merit can reach their maxim value.More specifically,the Seebeck coefficient can reach 6 k_B?e and figure of merit can reach 60 under good conditions.This result will benefit the design of high efficient thermal electrical converter.