Proposed Soft X-ray Beamlines
Last modified: 2010-02-15
This document is an attempt to create a
starting point for discussions concerning the
Soft X-ray beamlines at MAX IV. It is
not a final description of what will happen. As
obvious this document is very much in an "under construction" phase.
General principles
The CDR has been the starting point regarding beamlines and scientific case(s).
Most beamlines have at least two branches/experimental stations.
Off beamline equipment for preparation and characterization is important. This may be SEM, AFM and STM for
characterization of the structure on various length scales as well as other equipment for e.g. electrical
measurements. Also some preparation facilities are needed. It would be beneficial if samples can be transferred
from here to the experimental stations under vacuum, i.e. using vacuum suitcases.
Some beamlines may benefit much from an integrated STM or AFM for simple sample characterization.
Standardize as much as possible; sample-holders, transfer systems, manipulators, monochromators etc.
We may have to change the refocusing optics for some of the relocated beamlines but in most cases it may be reusable.
"Transferred" means "transferred to the1.5 GeV ring"
Last modified: 2010-02-18
Reference group
A group has been formed in order to create a coordinated effort on soft X-ray beamlines and techniques at
MAX IV and to provide local contact points for the initial stage of the process. The group is composed of:
Jesper N Andersen, jesper.andersen@sljus.lu.se, Lund University, Chair
Magnus Skoglund, skoglund@chalmers.se, Chalmers University
Mats Göthelid, gothelid@kth.se, Royal Institute of Technology
Franz Hennies, franz.hennies@maxlab.lu.se, MAX-lab and Uppsala University
Svante Svensson, svante.svensson@fysik.uu.se, Uppsala University
Olof (Charlie) Karis olof.karis@fysik.uu.se, Uppsala University
Ib Chorkendorff, ibchork@fysik.dtu.dk, Technical University of Denmark
Janusz Kanski, janusz.kanski@chalmers.se, Chalmers University
Anders Sandell, anders.sandell@fysik.uu.se, Uppsala University
Oscar Tjernberg, oscar@kth.se, Royal Institute of Technology
Edwin Kukk, ekukk@utu.fi, Turku University, Finland
Roger Uhrberg, rub@ifm.liu.se, Linköping University
Mika Valden, mika.valden@tut.fi, Tampere University of Technology, Finland
Anne Borg, anne.borg@phys.ntnu.no, NTNU, Norway
Lars Johansson, lars.johansson@kau.se, Karlstad University
Georg Held, g.held@reading.ac.uk, Reading University, UK
Bogdan Kowalski, kowab@ifpan.edu.pl, Polish Academy of Sciences, Poland
Vytautas Karpus, karpus@pfi.lt, Semiconductor Physics Institute, Vilnius, Lithuania
Researchers with an interest in soft X-ray developments at MAX IV should contact this group either via their local contacts or by e-mailing
Jesper N Andersen
Writing groups
For each soft X-ray and VUV beamline in the list below we have now defined "writing
groups" which are in the process of preparing the proposals. Names and contact details
of the person(s) in charge of these groups for the individual beamline proposals are given
after the description of each beamline.
The (expected) situation at MAX II at the time of completion of MAX IV
I511:
New undulator, EPU.
New monochromator (collimated PGM) with new low energy RIXS and new High Pressure Photoemission endstations.
This is funded by two separate Wallenberg donations. We denote this "511new".
The old 511 monochromator will be in storage. The current endstations will be in storage The old planar undulator
will be in storage. We denote this "511old".
I411:
As today for gas-phase and "dirty matter" (outgassing samples, liquids).
I311:
As today (Scienta + PEEM endstations) but with a new planar undulator lattice. Most likely the PEEM will have been
upgraded with aberration correction (better transmission, better spatial resolution)
D1011:
As today. Note that the monochromator is not water-cooled thus it can only use a bend magnet.
I1011:
As today plus equipment for coherent scattering and imaging.
Last modified: 2010-02-15
Beamline 1 (new) Microscopy and Spectroscopy
Elliptically Polarized Undulator
The
spot size should be as small as possible but also allow uniform illumination of an at least 20x20 micrometer spot. To get to so small spot size we need a 2-stage focusing solution at least for the horizontal focusing.
Flux should be maximized.
Energy range
from ca. 70 eV to 1 keV.
End stations:
1) PEEM
The PEEM is the existing one at 311 (upgraded with aberration correction) Spatial resolution should get into the 1-2 nm range with this upgrade.
The
energy resolution of the PEEM is now below 100 meV which should be matched by the monochromator at least up to 400 eV. Very much points to a CPGM with 1200 and 3-400 lines gratings)
2) Spectroscopy (Photoemission, XAS, CMD) Very good UHV
The improved performance of the CPGM (compared to the old MAX II PGM) monochromator of this beamline is needed for continuing the strong Swedish tradition in high resolved electron spectroscopies into the future.
New large hemispherical analyzer with possibilities for angle resolved mode, detectors on the hemispherical analyzer need to be discussed (e.g., spin detection).
XAS detectors etc.
It would be good if samples can be transferred under vacuum to and from the PEEM end station.
3) A
STXM could be put at a 3rd branch
Contact persons
Alexei Zakharov, MAX-lab
Karina Schulte, MAX-lab (XSTM)
Last modified: 2010-02-15
Beamline 2 (transferred) RIXS and High Pressure Photoemission
Elliptically Polarized Undulator
This is the 511 new beamline and endstations. The undulator should be new in order to make use of the slightly longer straight sections, in particular if the 511 new EPU can be used at another beamline. Note that the high pressure photoemission endstation also allows measurements with UHV in the 10
-10 torr range.
Contact persons
Franz Hennies, MAX-lab
Hans Siegbahn, Uppsala University
Last modified: 2010-02-15
Beamline 3 (transferred to the 3GeV ring)
What exists at
I1011 at the time of the move
+ A new PEEM inclusive the refocusing optics needed to get to a very small light spot (micron size) in order to increase the flux per area. The 3 GeV ring has a smaller beam size thus focusing to small spot size is easier and most importantly the 1st harmonic of the undulator goes up to 1 keV so one can get 100% circularly polarized light at higher photon energies than at the 1.5 GeV ring.
+ A second branch for coherent imaging/diffraction and "non-coherent" diffraction/reflectivity with magnetic contrast.
Contact person
Matts Björck, MAX-lab
Last modified: 2010-02-15
Beamline 4 (NEW at the 3 GeV ring) for Gas-phase
Using the high brilliance of the 3.0 GeV ring, one beamline will cover the higher energy range (˜200-2000 eV) with extremely high resolution (resolving power > 10
5 at lower energy limit). This beamline will provide variable polarization radiation from an elliptically polarizing undulator. This beamline will have a permanent endstation with a high-resolution electron spectrometer, with optional spin-resolving detector. There will also be provisions to allow users to mount their own experiments, e.g. coincidence set-ups or X-ray emission and photon fluorescence end stations, at the beamline
Contact person
Edwin Kukk, Turku University
Last modified: 2010-02-15
Beamline 5 (NEW at the 3 GeV ring) Very High Resolution Soft X-ray Spectroscopy
The beamline is optimized to deliver high intensity, sharply monochromatized X-rays in the
range 250 to 1000 eV with variable polarization, making full use of the very low emittance
of the 3 GeV storage ring. Emphasis is on resonant inelastic X-ray scattering at variable
polarisation and very high resolution for first row elements at the K edge, 3d transition
elements at the L edge, for lanthanides at the M edge, and for actinides at the N edge.
This beamline will enable several new activities in applied and fundamental research, nanoscience, and materials science, as well as related disciplines.
At the 2007 Workshop "Science at MAX IV" the localisation of an ARPES branchline was proposed, due to the highly similar demands on beamline performance as well as to the expected synergies for the user community.
Energy (wavelength) range |
250 - 1200 eV (using the 1st harmonic). |
Energy resolution |
Resolving power 50 000 @500eV to 20 000 @1000eV |
Photon source |
Elliptically Polarising Undulator |
Monochromator |
Plane Grating Monochromator (PGM) with refocusing optics.
Combination of flat, cylindrical and toroidal mirrors, cooled
where necessary. |
Beam size at sample |
~1x1 μm2 with refocusing optics |
Equipment |
RIXS:
Soft X-ray spectrometer, designed to take full advantage of the
small sample spot, and to attain the highest transmission and
resolving power.
ARPES:
TBD. |
Contact persons
Jan-Erik Rubensson, Uppsala University
Oscar Tjernberg, Royal Institute of Technology (KTH)
Last modified: 2010-02-11
Beamline 6 Ultrasoft X-ray Scattering Beamline
Ultrasoft X-ray scattering beamline:
Low-energy (20-250 eV) at the 1.5 GeV ring at MAX IV [3p edges of TM:s, Si 2p, Al 2p, S 2p, 4d lanthanides, 5d actenides].
Description
This beamline is designed to deliver ultra-high resolution, high intensity X-rays in the range
20 to 250 eV with variable polarization making full use of the very low emittance of the 1.5
GeV storage ring. The emphasis is on resonant inelastic X-ray scattering (RIXS) with variable
polarization and meV resolution for photon energies covering the M edges of the 3d transition
elements, the 4d edges of the rare earths and the 5d edges of the actinides as well as the 2p
edges of Al, Si and S. The beamline should also provide a very competitive source for new
activities for several new activities in applied and fundamental research, nanoscience, materials
science, chemical physics and related disciplines.
The beamline should be provided with a monochromator with very high resolution (1 meV @ 75 eV
and better than 10 meV at 250 eV) and a refocusing arrangement that yields a spot of the order
of 1 micron. The optical design needs to be such that the photon energy distribution over the
beam on the sample is as sharp as possible without pronounced tails in order to resolve very
low energy loss features close to the elastic scattering signal.
Technical data
Energy or wavelength range: |
20-250 eV |
Energy resolution: |
100000@100 eV |
Source: |
Elliptically Polarizing Undulator (EPU) |
Flux at first optical elements: |
1x1016 photons/s/0.1%bw for 500 mA stored current |
Optics: |
Plane Grating Monochromator (PGM) with refocusing
optics. Combination of flat, cylindrical and toroidal mirrors, cooled where necessary. |
Sample Environment: |
High and Ultrahigh Vacuum is necessary. Cooling and heating
sample stage. Preparation chamber with sputtering and heating. |
Beam size at sample: |
1x1microns with refocusing optics |
Flux on sample: |
1x1014 photons/s/0.1%bw |
Detectors: |
Soft X-ray spectrometer, designed to take full advantage of
the small sample spot and photon flux to attain the highest transmission and resolving power
in the low-energy range. |
Polarization: |
Variable circular, elliptical and linear |
Contact person
Martin Magnusson , Linköping University
Last modified: 2010-02-11
Beamline 7 New Beamline for PEEM/NanoXPS and XMCD
We suggest an undulator beamline that offers PEEM/NanoXPS combined with XMCD.
Important is to explore the possibility to vary the flux. NanoXPS requires a minimum
of 10
12 photons/mm
2sec (which the BL should cover) and the beamline should allow for XMCD measurements of molecular layers that are susceptible towards radiation damage.
Contact person
Anders Sandell , Uppsala University
Relocated Soft X-ray Beamlines
Last modified: 2010-02-18
For the “solid state” beamlines we have 2 water cooled SX700’s (I311 and I511old)
~3 end stations (D1011, I311 Scienta, I511 surface science station) with the comment that the I311
Scienta analyzer has a non-optimum lens system with lower solid angle acceptance and worse angular resolution.
Thus this analyzer should be decommissioned.
The new undulators at I311 (planar) and I511 (EPU) can most likely also be used.
These components can be combined in new ways and new instrumentation can be added.
Below is one suggestion:
D1011 transferred
Photoemission and absorption spectroscopy.
This goes on a bend magnet.
The existing D1011 Scienta endstation + possible upgrade of XAS detectors. Note that there will be no bump,
thus there will be only linearly polarized light. The use of a dipole magnet is beneficial to radiation
sensitive systems and for all types of absorption measurements that include scanning the photon energy.
It is possible to put in a second branch by going straight through the experimental chamber should be kept open.
Branching before the first experimental chamber does not seem realistic due to the monochromator optics.
Contact person
Anders Sandell, Uppsala University
I311 monochromator transferred
Planar undulator (The new I311 undulator could be used)
Endstations:
1) A surface science station
Combining equipment and ideas from the I311 Scienta chamber with, for instance, the newer Scienta analyzer from 511.
This should be a simple to use chamber with a differential pumping like at I311 towards the beamline. It might be
interesting to include a molecular beam for gas-dosing including of course possibilities for exciting the molecules
in the gas with e.g, lasers.
2) A new high pressure photoemission end station.
This end station will also allow UHV measurements in the 10-10 torr range.
It has been suggested that this beamline is moved to the 3 GeV ring due to the large increase in
intensity at photon energies around 1 keV. This solution will require a new monochromator and a new
undulator. These will be similar to those at Beamline 4 and Beamline 5 described above with an energy range
of 200-2000 eV. This 3 GeV solution is the preferred working option at present.
Contact person
Joachim Schnadt, Lund University
I511 old monochromator transferred
Elliptically Polarized Undulator (before the closing of operation of MAX II we use the old planar
I511 undulator, later we change to the 511new EPU). Not requesting 100% polarization (and using the 5th undulator harmonic)
of the light should make it possible to get up about 1 keV in non-linear polarization experiments.
Endstations:
1) The magnetic chamber from D1011 could be put here with possibilities for XMCD and element-specific
hysteresis measurements (electron and/or photon detection).
2) Photoemission system using a large hemispherical analyzer and including a fully motorized and
automated goniometer to also facilitate band mapping
or photoemission and X-ray Emission Spectroscopy system directed towards samples of more "applied" nature.
3) Coherent imaging/diffraction facility. Because of the lower amount of coherent radi1tion at
the 1.5 GeV ring this will have lower performance than on the 3 GeV ring. Still it will be a valuable test facility
and should also be sufficient for many experiments.
Contact person
Lars Johansson, Karlstad University
I411 Gas-phase transferred
At the 1.5 GeV ring, gas phase activities will continue at a relocated I411 beamline, using the same undulator, optics,
and endstation. This will facilitate a fast start of these activities at the new ring. The focus will here be on the
lower energy range, covering the important range covering the K-edge of Li, relevant for battery research, the L-edge
of Si, etc.
Contact person
Maxim Tchaplyguine, MAX-lab
