PHELIX is a beamline using soft X-rays, the source of which is an APPLE II undulator with permanent magnets.

This type of insertion device gives the opportunity to obtain a variable polarization of light: linear polarization at any angle as well as circular and elliptical polarization.

The PHELIX end-station enables a wide range of spectroscopic and absorption studies characterized by different surface sensitivity. Besides collecting standard high-resolution spectra, it allows, e.g. to map the band structure in three dimensions and to detect the spin in three dimensions.

The main components of the PHELIX end-station are as follows:

• well-equipped analysis chamber with hemispherical photoelectron energy analyzer with resolution ~1 meV, 3D spin detector VLEED-type, total fluorescence detector and additional sources of radiation (X, UV) enabling operation without a beam,
• preparation chamber with effusion cells and EBVs for in situ thin layers deposition with precise control of their thickness, LEED diffractometer, leak valves enabling operation with various gases and a sample stage allowing samples to be heated up to 2000°C,
• crystal cleaver chamber allowing to expose atomically smooth surfaces under ultra-high vacuum conditions.

Application:

• new materials for spintronics and magnetoelectronics, topological insulators
• thin films and multilayers systems including samples obtained in-situ
• surface of bulk compounds
• surface magnetism, spin polarized surface states
• chemical reactions taking place on the surface
• biomaterials.​​

​The beamline team:

• prof. dr. hab. Jacek Szade, the SOLARIS Centre / the University of Silesia in Katowice
• dr eng. Magdalena Szczepanik, the SOLARIS Centre
• dr Ewa Partyka-Jankowska, the SOLARIS Centre
• mgr Tomasz Sobol, the SOLARIS Centre.​

​Beamline optical scheme:

Beamline parameters:

Radiation source	elliptically polarizing undulator (EPU), APPLE II type with permanent magnets
Photon energy range (using the energy of the electrons in the storage ring of 1.5 GeV	50–1500 eV for linear horizontal, linear vertical, and circular polarization 70–1500 eV for linear polarization inclined at 45°
Maximum resolving power	> 10 000
The maximum size of the excited area on the sample	100 µm x 100 µm with the resolving power (RP) ≥ 10 000 over the entire energy range and for all polarizations
Photon flux on the sample	≥ 1×1013 photons/s/0.1% B.W. for 50 eV and ≥ 1×1011 photons/s/0.1% B.W.  for 1500 eV, for maximum RP and electron current in the storage ring (500 mA)
Controlled polarization	variable linear, circular and elliptical
Available techniques	PES (ResPES, ARPES, SX-ARPES, SR-ARPES, XPS, UPS, CD-ARPES), XAS (TFY, TEY)

 

Publications:

PHELIX – A new soft X-ray spectroscopy beamline at SOLARIS synchrotron
Magdalena Szczepanik-Ciba, Tomasz Sobol, Jacek Szade
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms,
Volume 492, Pages 49-55, 1 April 2021,
DOI: 10.1016/j.nimb.2021.01.021