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Title: Probing ultra-fast processes with high dynamic range at 4th-generation light sources: Arrival time and intensity binning at unprecedented repetition rates

Abstract

Here, understanding dynamics on ultrafast timescales enables unique and new insights into important processes in the materials and life sciences. In this respect, the fundamental pump-probe approach based on ultra-short photon pulses aims at the creation of stroboscopic movies. Performing such experiments at one of the many recently established accelerator-based 4th-generation light sources such as free-electron lasers or superradiant THz sources allows an enormous widening of the accessible parameter space for the excitation and/or probing light pulses. Compared to table-top devices, critical issues of this type of experiment are fluctuations of the timing between the accelerator and external laser systems and intensity instabilities of the accelerator-based photon sources. Existing solutions have so far been only demonstrated at low repetition rates and/or achieved a limited dynamic range in comparison to table-top experiments, while the 4th generation of accelerator-based light sources is based on superconducting radio-frequency technology, which enables operation at MHz or even GHz repetition rates. In this article, we present the successful demonstration of ultra-fast accelerator-laser pump-probe experiments performed at an unprecedentedly high repetition rate in the few-hundred-kHz regime and with a currently achievable optimal time resolution of 13 fs (rms). Our scheme, based on the pulse-resolved detection of multiplemore » beam parameters relevant for the experiment, allows us to achieve an excellent sensitivity in real-world ultra-fast experiments, as demonstrated for the example of THz-field-driven coherent spin precession.« less

Authors:
 [1];  [1];  [2];  [3];  [2];  [4];  [3];  [1]
  1. Helmholz Zentrum Dresden Rossendorf, Dresden (Germany)
  2. Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
  3. Fritz-Haber-Institut der Max Planck Gesellschaft, Berlin (Germany)
  4. SLAC National Accelerator Lab., Menlo Park, CA (United States)
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1368582
Grant/Contract Number:
AC02-76SF00515
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Structural Dynamics
Additional Journal Information:
Journal Volume: 4; Journal Issue: 2; Journal ID: ISSN 2329-7778
Publisher:
American Crystallographic Association/AIP
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY

Citation Formats

Kovalev, S., Green, B., Golz, T., Maehrlein, S., Stojanovic, N., Fisher, A. S., Kampfrath, T., and Gensch, M.. Probing ultra-fast processes with high dynamic range at 4th-generation light sources: Arrival time and intensity binning at unprecedented repetition rates. United States: N. p., 2017. Web. doi:10.1063/1.4978042.
Kovalev, S., Green, B., Golz, T., Maehrlein, S., Stojanovic, N., Fisher, A. S., Kampfrath, T., & Gensch, M.. Probing ultra-fast processes with high dynamic range at 4th-generation light sources: Arrival time and intensity binning at unprecedented repetition rates. United States. doi:10.1063/1.4978042.
Kovalev, S., Green, B., Golz, T., Maehrlein, S., Stojanovic, N., Fisher, A. S., Kampfrath, T., and Gensch, M.. Mon . "Probing ultra-fast processes with high dynamic range at 4th-generation light sources: Arrival time and intensity binning at unprecedented repetition rates". United States. doi:10.1063/1.4978042. https://www.osti.gov/servlets/purl/1368582.
@article{osti_1368582,
title = {Probing ultra-fast processes with high dynamic range at 4th-generation light sources: Arrival time and intensity binning at unprecedented repetition rates},
author = {Kovalev, S. and Green, B. and Golz, T. and Maehrlein, S. and Stojanovic, N. and Fisher, A. S. and Kampfrath, T. and Gensch, M.},
abstractNote = {Here, understanding dynamics on ultrafast timescales enables unique and new insights into important processes in the materials and life sciences. In this respect, the fundamental pump-probe approach based on ultra-short photon pulses aims at the creation of stroboscopic movies. Performing such experiments at one of the many recently established accelerator-based 4th-generation light sources such as free-electron lasers or superradiant THz sources allows an enormous widening of the accessible parameter space for the excitation and/or probing light pulses. Compared to table-top devices, critical issues of this type of experiment are fluctuations of the timing between the accelerator and external laser systems and intensity instabilities of the accelerator-based photon sources. Existing solutions have so far been only demonstrated at low repetition rates and/or achieved a limited dynamic range in comparison to table-top experiments, while the 4th generation of accelerator-based light sources is based on superconducting radio-frequency technology, which enables operation at MHz or even GHz repetition rates. In this article, we present the successful demonstration of ultra-fast accelerator-laser pump-probe experiments performed at an unprecedentedly high repetition rate in the few-hundred-kHz regime and with a currently achievable optimal time resolution of 13 fs (rms). Our scheme, based on the pulse-resolved detection of multiple beam parameters relevant for the experiment, allows us to achieve an excellent sensitivity in real-world ultra-fast experiments, as demonstrated for the example of THz-field-driven coherent spin precession.},
doi = {10.1063/1.4978042},
journal = {Structural Dynamics},
number = 2,
volume = 4,
place = {United States},
year = {Mon Mar 06 00:00:00 EST 2017},
month = {Mon Mar 06 00:00:00 EST 2017}
}

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