The BACH beamline belongs to the Istituto Officina dei Materiali (IOM) of the Consiglio Nazionale delle Ricerche (CNR) and it is operated by a CNR team in collaboration with Elettra-Sincrotrone Trieste S.C.p.A.
Research highlights | Publications
In the UHV (low 10-10 mbar) endstation of the BRANCH A it is possible to perform a multi-spectroscopy investigation with photoemission UPS/XPS (including polarization and photon energy-dependent ultra-violet (UV) and soft-x SX-ARPES (SEE FIGURE), RESPES and energy-dependent Photoelectron DIffraction PhD), x-ray absorption XAS (TEY,PEY,TFY,PFY) including GAP SCAN acquisitions, x-ray emission XES and x-ray magnetic circular dichroism XMCD (in remanence in the branch A). A LEED and several electron beam evaporators are available to deposit selected metals on the sample surface at different temperatures. A sample-preparation UHV chamber, directly connected to the EndstationA can be used to grow thin films of metals or metal oxides and deposit organic/inorganic molecules, hybrid systems or magnetic elements on solid surfaces for in-situ investigations.
The experimental setup of the BRANCH A can also combine Laser and Synchrotron Radiation (SR) in order to study the dynamics of the photo-induced excited states of electronic and magnetic systems with optical pump- x ray probe time-resolved XAS. Elettra Synchrotron radiation source provides radiation pulse widths sufficiently short to investigate dynamic processes in the time between 70 ps up to 0.5 μs. Typically, optical excitation of the sample is done by laser pulses (synchronized to either hybrid or multi bunch SR pulses), and probing is performed by time-delayed synchrotron radiation pulses.
The experimental setup of the BRANCH B hosts a new endstation dedicated to x-ray magnetic circular dichroism in high magnetic fields (± 6.5 Tesla, ramp rate of 1T/min) along the beam and variable tempertaure from 1.8 K to 340 K on the sample in a base pressure of 1.2x10-11 mbar (only by cryopumping). A sample UHV preparation chamber with a LEED, cleaving and scraping facilities, possibility to install evaporators without breaking the UHV has been assembled, installed and already tested and used for a first in-situ XMCD experiment (May 2014. The first XMCD measurements with the new cryomagnet at low T (4 K) under high magnetic fields have been obtained during the commissioning (March 2013, sample courtesy of J. Fontcuberta). The endstation can be used to measure XMCD both under applied magnetic fields and in remanence.
DUE TO THE LACK OF FUNDS FOR PURCHASING LHe THIS ENDSTATION WILL NOT BE AVAILABLE.
A third BRANCH C is also available for the installation of user endstations for long term projects.
VG-Scienta R3000 analyser (Dichroic EUV-SX-RES-ARPES, RESPES, fast XPS and UPS, PhD, partial yield XAS)
A VG-Scienta hemispherical electron analyzer (CNR) has been installed in mid December 2011 on the branch A, replacing the VSW 150 mm analyser (Elettra - Sincrotrone Trieste S.C.p.A.).This instrument offers the possibility to perform angle-resolved photoemission (ARPES) with energy resolution better that 3 meV and angular resolution better than 0.1° and full control of the polarization in a wide photon energy range (from 35 to 1600 eV) for band mapping and surface structural studies. This instrument can be used to perform polarization and photon energy dependent ARPES from the Extreme UV to the Soft X ray range (35-1600eV). In particular RES SX ARPES can be performed for example at resonance of transition metals L23 edge.
A quick acquisition mode is available to perform Fast XPS/UPS/ARPES, e.g. during chemical reactions, with 320 msec total acquisition time per spectrum.|
The same instrument can be used to acquire Partial Yield XAS (secondary or Auger electrons), together with the drain current from the sample (TEY). Gap-scan partial yield XAS is also possible.
Resonant Photoemission and Energy dependent Photoelectron Diffraction spectra are acquired in a full automatized mode since the instrument has been interfaced to the monochromator and undulators of the beamline.
Please contact F. Bondino and E. Magnano for details.
Gap Scan Operation Mode
“Gap/Phase Energy scan” acquisition mode (synchronization of the undulator gap and phase with the monochromator) has been implemented to XAS, XMCD, RESPES, ARPES and PhD. This has been possible thanks to the collaboration with undulator group (D. Millo, ST), Undulator server group (L. Pivetta, L. Scafuri, ST), A. Barla (ISM-CNR), L. Stebel (ST)
Before submitting a proposal for the BACH beamline we invite user to read the Info for Users and this page to have an updated information on the endstations and instrumentation. In any case we invite users and collaborators to discuss their proposals with the beamline local contacts well in advance before the submission deadline. This is crucial for a careful assessment of the experiment feasibility and may lead to improvements in the proposed experimental plan. We invite users interested in installing a bulky piece of equipment (such as an entire experimental station) which takes a long time to assemble and dismount to discuss their project with the beamline local contacts well in advance before the submission deadline.
September 15th, 2015
for proposals eligible for the user period starting from January 1st to June 30th, 2016
Any person working at the BACH beamline has to read and follow the safety rules described here before accessing the beamline BACH Safety Rules