Thermodynamic study of multilayer Dirac electron system

在实现线性色散的无质量狄拉克费米子体系的压力下，测量了有机导体α-(BEDT-TTF)_2I_3的比热。在低温时，比热几乎表现为∝T^2依赖性，在磁场中表现为峰值和饱和。通过假设狄拉克费米子系统的线性色散和N=0朗道能级特征，可以很好地理解这些行为。结果也与报道的磁电阻相当一致。

We have measured the specific heat of the organic conductor α-(BEDT-TTF)_2I_3 under pressure where the massless Dirac fermion system with linear energy dispersion is realized. In low temperature, the specific heat shows almost ∝T^2 dependence, and shows the peak and saturation in magnetic field. These behaviors are well understood by assuming the linear dispersion and N=0 Landau level characteristic of the Dirac fermion system. The results are also quite consistent with the reported magnetoresistance.