Ultrafast quasiparticle relaxation dynamics in normal metals and heavy-fermion materials

被引：34

作者：

Ahn, KH ^{[1
]}

Graf, MJ ^{[1
]}

Trugman, SA ^{[1
]}

Demsar, J ^{[1
]}

Averitt, RD ^{[1
]}

Sarrao, JL ^{[1
]}

Taylor, AJ ^{[1
]}

机构：

[1] Los Alamos Natl Lab, Los Alamos, NM 87545 USA

来源：

PHYSICAL REVIEW B | 2004年 / 69卷 / 04期

关键词：

D O I：

10.1103/PhysRevB.69.045114

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We present a detailed theoretical study of the ultrafast quasiparticle relaxation dynamics observed in normal metals and heavy-fermion materials with femtosecond time-resolved optical pump-probe spectroscopy. For normal metals, a nonthermal electron distribution gives rise to a temperature- (T) independent electron-phonon relaxation time at low temperatures, in contrast to the T-3-divergent behavior predicted by the two-temperature model. For heavy-fermion compounds, we find that the blocking of electron-phonon scattering for heavy electrons within the density-of-states peak near the Fermi energy is crucial to explain the rapid increase of the electron-phonon relaxation time below the Kondo temperature. We propose the hypothesis that the slower Fermi velocity compared to the sound velocity provides a natural blocking mechanism due to energy and momentum-conservation laws.

引用

页数：9

共 22 条

[1] THEORY OF THERMAL RELAXATION OF ELECTRONS IN METALS [J].