2013/08/31 by V. V. Baranov, V. V. Kabanov · 2 citations
Chemistry · Engineering · Materials Science · Physics and Astronomy · #Atomic physics #Chemistry #Condensed matter physics #Electron #Electronic and Structural Properties of Oxides #Excited state #Kinetic energy #Molecular Junctions and Nanostructures #Phonon #Physics #Quantum mechanics #Relaxation (psychology) #Spectroscopy and Quantum Chemical Studies #Thermalisation #Vibrational energy relaxation #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.89.125102
published as Phys. Rev. B 89, 125102 (2014) · 9 pages, 6 figures
openalex publication_date 2014/03/04 · arxiv created 2014/03/05 · arxiv updated 2014/03/06 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The theory of the electron relaxation in simple metals excited by an ultrashort optical pump is developed on the basis of the solution of the linearized Boltzmann kinetic equation. The kinetic equation includes both the electron-electron and the electron-phonon collision integrals and assumes that Fermi liquid theory is applicable for the description of a simple metal. The widely used two-temperature model follows from the theory as the limiting case when the thermalization due to the electron-electron collisions is fast with respect to the electron-phonon relaxation. It is demonstrated that the energy relaxation has two consecutive processes. The first and most important step describes the emission of phonons by the photoexcited electrons. It leads to the relaxation of 90% of the energy before the electrons become thermalized among themselves. The second step describes electron-phonon thermalization and may be described by the two-temperature model. The second stage is difficult to observe experimentally because it involves the transfer of only a small amount of energy from electrons. Thus the theory explains why the divergence of the relaxation time at low temperatures has never been observed experimentally.