Demsar Jure, Thorsmølle Verner K, Sarrao John L, Taylor Antoinette J
Jozef Stefan Institute, Jamova 39, SI-1000, Ljubljana, Slovenia.
Phys Rev Lett. 2006 Jan 27;96(3):037401. doi: 10.1103/PhysRevLett.96.037401. Epub 2006 Jan 24.
We have studied the photoexcited carrier relaxation dynamics in the Kondo insulator SmB6 and the heavy fermion metal YbAgCu4 as a function of temperature and excitation level. The dynamic response is found to be both strongly temperature dependent and nonlinear. The data are analyzed with a Rothwarf-Taylor bottleneck model, where the dynamics are governed by the presence of a narrow gap in the density of states near the Fermi level. The remarkable agreement with the model suggests that carrier relaxation in a broad class of heavy electron systems (both metals and insulators) is governed by the presence of a (weakly temperature dependent) hybridization gap.
我们研究了近藤绝缘体SmB6和重费米子金属YbAgCu4中光激发载流子的弛豫动力学与温度和激发水平的关系。发现动态响应强烈依赖于温度且是非线性的。用Rothwarf-Taylor瓶颈模型对数据进行了分析，其中动力学由费米能级附近态密度中的窄能隙决定。与该模型的显著吻合表明，一大类重电子系统（包括金属和绝缘体）中的载流子弛豫受（弱温度依赖的）杂化能隙的影响。
