过渡金属锡化物RhSn_3的磁电阻研究

Magnetoresistance in the Transition-metal Stannide RhSn3

具有大磁阻效应的材料广泛运用在实际生活中,因此对这些材料的研究具有重要的科学意义和现实意义.该论文通过实验发现,与一般金属不同,二元过渡金属锡化物RhSn3单晶样品具有很大的磁电阻效应.在T=2K,B=9T时,磁电阻达到近400%.并且,与一般金属中B2的电阻-磁场依赖关系不同,RhSn3的磁阻与磁场的关系近似满足线性行为.这一线性磁阻与Dirac半金属或Weyl半金属中的线性磁阻具有很多相似性.进一步的分析表明,该样品的磁阻在很大的磁场和温度范围内都很好的符合Kohler定理.综合以上实验结果,我们认为RhSn3样品中的载流子具有很高的迁移率,并且载流子浓度并不随温度显著的变化.至于该样品中是否也存在Dirac电子,还需要进一步的实验和理论研究.

Materials with large magnetoresistance have attracted tremendous interest not only because of its fundamental scientific importance,but also due to its broad application in reality.This paper reports on the large,quasi-linear magnetoresistance in the binary transition-metal based stannide RhSn3 single crystal.When T=2 K and B= 9 T,the magnetoresistance of RhSn3 reaches as high as 400%.Different from the dependency relation between the magnetoresistance and magnetic field of B2 in general metals,the relation between the magnetoresistance and magnetic field of RhSn3 is similar to linear behavior.In contrast to the quadratic in field magnetoresistance in standard metals,the magnetoresistanc of RhSn3 is quasi-linear in field which resembles the behaviors found in Dirac or Weyl semimetals.Moreover,it is further found that the semi-classical Kohlers rule is well obeyed in this material.These results seem to argue against the remarkable loss of carriers with decreasing temperature or strange anisotropic scattering on the Fermi surface in this material.Whether Dirac fermions are responsible for the linear magnetoresistance observed here remains to be studied in the future.