Dynamics of Excited Electrons in Copper and Ferromagnetic Transition Metals: Theory and Experiment
- Both theoretical and experimental results for the dynamics of photoexcited electrons at surfaces of Cu and the ferromagnetic transition metals Fe, Co, and Ni are presented. A model for the dynamics of excited electrons is developed, which is based on the Boltzmann equation and includes effects of photoexcitation, electron-electron scattering, secondary electrons (cascade and Auger electrons), and transport of excited carriers out of the detection region. From this we determine the time-resolved two-photon photoemission (TR-2PPE). Thus a direct comparison of calculated relaxation times with experimental results by means of TR-2PPE becomes possible. The comparison indicates that the magnitudes of the spin-averaged relaxation time t and of the ratio t_up/t_down of majority and minority relaxation times for the different ferromagnetic transition metals result not only from density-of-states effects, but also from different Coulomb matrix elements M. Taking M_Fe > M_Cu > M_Ni = M_Co we get reasonable agreement with experiments.
Author: | M. Aeschlimann, R. Knorren, K.H. Bennemann, R. Burgermeister |
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URN: | urn:nbn:de:hbz:386-kluedo-11341 |
Document Type: | Preprint |
Language of publication: | English |
Year of Completion: | 2000 |
Year of first Publication: | 2000 |
Publishing Institution: | Technische Universität Kaiserslautern |
Date of the Publication (Server): | 2001/04/27 |
Faculties / Organisational entities: | Kaiserslautern - Fachbereich Physik |
DDC-Cassification: | 5 Naturwissenschaften und Mathematik / 530 Physik |
Licence (German): | Standard gemäß KLUEDO-Leitlinien vor dem 27.05.2011 |