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Attosecond photoelectron spectroscopy of electron transport in solids

Abstract

Time-resolved photoelectron spectroscopy of condensed matter systems in the attosecond regime promises new insights into excitation mechanisms and transient dynamics of electrons in solids. This timescale became accessible directly only recently with the development of the attosecond streak camera and of laser systems providing few-cycle, phase-controlled laser pulses in the near-infrared, which are used to generate isolated, sub-femtosecond extreme-ultraviolet pulses with a well-defined timing with respect to the near-infrared pulse. Employing these pulses, the attosecond streak camera offers time resolutions as short as a few 10 attoseconds. In the framework of this thesis, a new, versatile experimental apparatus combining attosecond pulse generation in gases with state of the art surface science techniques is designed, constructed, and commissioned. Employing this novel infrastructure and the technique of the attosecond transient recorder, we investigate transport phenomena occurring after photoexcitation of electrons in tungsten and rhenium single crystals and show that attosecond streaking is a unique method for resolving extremely fast electronic phenomena in solids. It is demonstrated that electrons originating from different energy levels, i.e. from the conduction band and the 4f core level, are emitted from the crystal surface at different times. The origin of this time delay, which is below 150  More>>
Publication Date:
Mar 31, 2011
Product Type:
Thesis/Dissertation
Report Number:
INIS-DE-1191
Resource Relation:
Other Information: TH: Diss.
Subject:
36 MATERIALS SCIENCE; BAND THEORY; CHARGE TRANSPORT; ELECTRON SPECTRA; ELECTRONIC STRUCTURE; EMISSION SPECTRA; EV RANGE 10-100; EV RANGE 100-1000; EXCITATION; F STATES; MONOCRYSTALS; PHOTOELECTRON SPECTROSCOPY; PHOTON COLLISIONS; PULSE TECHNIQUES; RHENIUM; SURFACES; TIME DEPENDENCE; TIME RESOLUTION; TUNGSTEN
OSTI ID:
21485518
Research Organizations:
Muenchen Univ. (Germany). Fakultaet fuer Physik
Country of Origin:
Germany
Language:
English
Other Identifying Numbers:
TRN: DE11FB457
Availability:
Commercial reproduction prohibited; INIS; OSTI as DE21485518
Submitting Site:
DEN
Size:
138 pages
Announcement Date:
Oct 27, 2011

Citation Formats

Magerl, Elisabeth. Attosecond photoelectron spectroscopy of electron transport in solids. Germany: N. p., 2011. Web.
Magerl, Elisabeth. Attosecond photoelectron spectroscopy of electron transport in solids. Germany.
Magerl, Elisabeth. 2011. "Attosecond photoelectron spectroscopy of electron transport in solids." Germany.
@misc{etde_21485518,
title = {Attosecond photoelectron spectroscopy of electron transport in solids}
author = {Magerl, Elisabeth}
abstractNote = {Time-resolved photoelectron spectroscopy of condensed matter systems in the attosecond regime promises new insights into excitation mechanisms and transient dynamics of electrons in solids. This timescale became accessible directly only recently with the development of the attosecond streak camera and of laser systems providing few-cycle, phase-controlled laser pulses in the near-infrared, which are used to generate isolated, sub-femtosecond extreme-ultraviolet pulses with a well-defined timing with respect to the near-infrared pulse. Employing these pulses, the attosecond streak camera offers time resolutions as short as a few 10 attoseconds. In the framework of this thesis, a new, versatile experimental apparatus combining attosecond pulse generation in gases with state of the art surface science techniques is designed, constructed, and commissioned. Employing this novel infrastructure and the technique of the attosecond transient recorder, we investigate transport phenomena occurring after photoexcitation of electrons in tungsten and rhenium single crystals and show that attosecond streaking is a unique method for resolving extremely fast electronic phenomena in solids. It is demonstrated that electrons originating from different energy levels, i.e. from the conduction band and the 4f core level, are emitted from the crystal surface at different times. The origin of this time delay, which is below 150 attoseconds for all studied systems, is investigated by a systematic variation of several experimental parameters, in particular the photon energy of the employed attosecond pulses. These experimental studies are complemented by theoretical studies of the group velocity of highly-excited electrons based on ab initio calculations. While the streaking technique applied on single crystals can provide only information about the relative time delay between two types of photoelectrons, the absolute transport time remains inaccessible. We introduce a scheme of a reference clock signal, i.e. a well-defined electronic state localised at the crystal surface, which enables us to measure the absolute time delay of photoelectrons, and present first results obtained on this system. (orig.)}
place = {Germany}
year = {2011}
month = {Mar}
}