SIS - X09LA: Surface / Interface Spectroscopy
The Surface/Interface Spectroscopy (SIS) beamline provides a state-of-the-art experimental set-up to study the electronic band structure of novel complex materials by spin- and angle-resolved photoemission spectroscopies. The beamline operates in the energy range from 20 to 800 eV with high flux, high resolution, variable polarization, and low high-harmonic contamination.
The beamline serves two endstations:
- ULTRA (Ultra Low-Temperature high-Resolution ARPES)
for angle-resolved photoelectron spectroscopy (ARPES) - COPHEE (Complete PHotoEmission Experiment)
for spin- and angle-resolved photoelectron spectroscopy (SARPES)
Users can apply for beamtime with the provided endstations or with their own endstation (after prior consultation with the beamline scientist).
| Energy range | 20 - 800 eV |
|---|---|
| Resolving power (E/Δ E) | 104 |
| Polarization | linear horizontal (20 - 800 eV) linear vertical (40 - 800 eV) circular left/right (50-800 eV) |
| Flux on sample (200 eV) | 2*1013 ph/s/0.1%BW/0.4 A |
| Higher order mode contamination | < 0.1 % |
| Spot size on sample (200 eV) | 50 x 100 µm2 (FWHM) |
Current Highlights and News
Unpaired Weyl Point observed for the first time in crystalline solid
Flows need sources and sinks. That’s why, in a new class of exotic materials called Weyl semimetals, the sources and sinks of Berry curvature – dubbed Weyl points – were believed to exist only in pairs. Now researchers at PSI have observed unpaired Weyl points for the first time in a crystalline solid. This discovery, which upends conventional thinking and the so-called Nielson-Niomiya no-go theorem, demonstrates the unique properties of "nodal wall" Weyl semimetals in comparison to conventional Weyl systems having only zero-dimensional Weyl nodes.
Creating novel quantum phases via the heterostructure engineering
Within this synergetic collaboration, PSI scientists have investigated the correlation between magnetic and electronic ordering in NdNiO3 by tuning its properties through proximity to a ferromagnetic manganite layer. The main outcome is that the stray magnetic field from the manganite layer causes a novel ferromagnetic-metallic (FM-M) phase in NNO. This work demonstrates the utilization of heterostructure engineering for creating novel quantum phases.
Novel structural orthorhombicity in an iron-pnictide superconductor
Researchers from University of Zurich describe the experimental observation of a new orthorhombic structural phase in the superconducting iron-pnictide compound Pr4Fe2As2Te0.88O4. In contrast to nematicity found in underdoped iron pnictides this phase transition is not electronically driven.