Kharzeev Dmitri E, Pisarski Robert D, Yee Ho-Ung
Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794-3800, USA.
Department of Physics, Brookhaven National Laboratory, Upton, New York 11973, USA.
Phys Rev Lett. 2015 Dec 4;115(23):236402. doi: 10.1103/PhysRevLett.115.236402. Epub 2015 Dec 2.
We investigate the properties of the collective plasmon excitations in Dirac semimetals by using the methods of relativistic field theory. We find a strong and narrow plasmon excitation whose frequency is in the terahertz (THz) range which may be important for practical applications. The properties of the plasmon appear universal for all Dirac semimetals, due to the large degeneracy of the quasiparticles and the small Fermi velocity, v_{F}≪c. This universality is closely analogous to the phenomenon of "dimensional transmutation" that is responsible for the emergence of dimensionful scales in relativistic field theories such as quantum chromodynamics.
我们通过使用相对论场论方法研究狄拉克半金属中集体等离激元激发的性质。我们发现一种强烈且狭窄的等离激元激发，其频率处于太赫兹（THz）范围，这可能对实际应用很重要。由于准粒子的高度简并性以及小的费米速度(v_{F}≪c)，等离激元的性质对于所有狄拉克半金属而言似乎是普遍的。这种普遍性与“维度转变”现象密切类似，“维度转变”现象导致了诸如量子色动力学等相对论场论中具有量纲的标度的出现。
