Change search
ReferencesLink to record
Permanent link

Direct link
Simulation of heat transfer in zone plate optics irradiated by X-ray free electron laser radiation
KTH, School of Engineering Sciences (SCI), Applied Physics, Biomedical and X-ray Physics.
KTH, School of Engineering Sciences (SCI), Applied Physics, Biomedical and X-ray Physics.ORCID iD: 0000-0003-2745-6289
KTH, School of Engineering Sciences (SCI), Applied Physics, Biomedical and X-ray Physics.ORCID iD: 0000-0002-4394-0591
2010 (English)In: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, Vol. 621, no 1-3, 620-626 p.Article in journal (Refereed) Published
Abstract [en]

Zone plates are high quality optics that have the potential to provide diffraction-limited nano-focusing of hard X-ray free electron laser radiation. The present publication investigates theoretically the temperature behavior of metal zone plates on a diamond substrate irradiated by 0.1 nm X-rays from the European X-ray Free Electron Laser. The heat transfer in the optic is simulated by solving the transient heat equation with the finite element method. Two different zone plate designs are considered, one small zone plate placed in the direct beam and one larger zone plate after the monochromator. The main result is that for all investigated cases the maximum temperature in the metal zone plate layer is at least a factor 2 below the melting point of the respective material, proving the efficiency of the proposed cooling scheme. However, zone plates in the direct beam experience large and rapid temperature fluctuations of several hundred Kelvin that might prove fatal to the optic. The situation is different for optics behind the monochromator with fluctuations in the 20 K range and maximum temperatures well below room temperature. The simulation results give valuable indications on the temperature behavior to be expected and are a basis for future experimental heat transfer and mechanical stability investigations of fabricated nanostructures.

Place, publisher, year, edition, pages
2010. Vol. 621, no 1-3, 620-626 p.
Keyword [en]
X-ray optics, Zone plate, XFEL, Heat transfer
National Category
Other Engineering and Technologies
URN: urn:nbn:se:kth:diva-26821DOI: 10.1016/j.nima.2010.03.115ISI: 000281109100092ScopusID: 2-s2.0-77957924973OAI: diva2:375509
QC 20101208Available from: 2010-12-08 Created: 2010-11-29 Last updated: 2013-05-14Bibliographically approved
In thesis
1. Zone Plates for Hard X-Ray Free-Electron Lasers
Open this publication in new window or tab >>Zone Plates for Hard X-Ray Free-Electron Lasers
2013 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Hard x-ray free-electron lasers are novel sources of coherent x-rays with unprecedented brightness and very short pulses. The radiation from these sources enables a wide range of new experiments that were not possible with previous x-ray sources. Many of these experiments require the possibility to focus the intense x-ray beam onto small samples. This Thesis investigates the possibility to use diffractive zone plate optics to focus the radiation from hard x-ray free-electron lasers.

The challenge for any optical element at free-electron laser sources is that the intensity in a single short pulses is high enough to potentially damage the optics. This is especially troublesome for zone plates, which are typically made of high Z elements that absorb a large part of the incident radiation. The first part of the Thesis is dedicated to simulations, where the temperature behavior of zone plates exposed to hard x-ray free-electron laser radiation is investigated. It is found that the temperature increase in a single pulse is several hundred Kelvin but still below the melting point of classical zone plate materials, such as gold, tungsten, and iridium.

Even though the temperature increases are not high enough to melt a zone plate it is possible that stresses and strains caused by thermal expansion can damage the zone plate. This is first investigated in an experiment where tungsten gratings on diamond substrates are heated to high temperatures by a pulsed visible laser. It is found that the gratings are not damaged by the expected temperature fluctuations at free-electron lasers. Finally, a set of tungsten zone plates are tested at the Linac Coherent Light Source where they are exposed to a large number of pulses at varying fluence levels in a prefocused beam. Damage is only observed at fluence levels above those typically found in an unfocused x-ray free-electron laser beam. At higher fluences an alternative is to use a diamond zone plate, which has significantly less absorption and should be able to survive much higher fluence. Damage in diamond structures is investigated during the same experiment, but due to a remaining tungsten etch mask on top of the diamond the results are difficult to interpret.

Additionally, we also demonstrate how the classical Ronchi test can be used to measure aberrations in focusing optics at an x-ray free-electron laser in a single pulse.

The main result of this Thesis is that tungsten zone plates on diamond substrates can be used at hard x-ray free-electron laser sources.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2013. xiii, 60 p.
Trita-FYS, ISSN 0280-316X ; 2013:14
X-ray optics, Zone plates, XFEL, x-rays, free-electron laser, heat transfer
National Category
Physical Sciences
urn:nbn:se:kth:diva-122161 (URN)978-91-7501-769-3 (ISBN)
Public defence
2013-05-31, FB 42, Albanova, Roslagstullsbacken 21, Stockholm, 10:15 (English)

QC 20130514

Available from: 2013-05-14 Created: 2013-05-13 Last updated: 2013-05-14Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Search in DiVA

By author/editor
Nilsson, DanielHolmberg, AndersVogt, Ulrich
By organisation
Biomedical and X-ray Physics
In the same journal
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
Other Engineering and Technologies

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 58 hits
ReferencesLink to record
Permanent link

Direct link