Facilities

High-resolution ARPES

6-axis cryogenic manipulator

 

sub-meV energy resolution
laser-based photoemission

We set up a high-resolution and low-temperature  ARPES system dedicated to the study of correlated electron systems. A list of  key capabilities is given below:

  • ARPES measurements are performed with a MBS-A1 hemispherical electron analyzer using a He discharge lamp with rotatable linear polarization and two complementary laser sources: an 11 eV laser by Lumeras and a 6.05 eV CW-laser from Leos Solutions that can be focused down to ~ 3 μm for microARPES experiments. The system has been optimized  to achieve routinely sub – meV energy resolution.
  • Photoemission experiments are performed in ultra-high vacuum ( p < 5 x 10-11 mbar), with the sample held on a fully-motorized custom-made 6-axis manipulator, where it can be cooled to 4 K.
  • Samples can be cleaved in-situ at the measurement temperature, and we also have capability to sputter and anneal samples in a dedicated preparation chamber. Deposition of elemental metals on the sample surface can be performed down to below 10 K, and surface structure and quality can be monitored by low-energy electron diffraction (LEED).

Additionally, our group has regular access to synchrotron radiation facilities in Europe where we perform complementary ARPES measurements (SIS and ADDRESS beamlines at the Swiss Light Source (CH), I05 at Diamond Light Source (UK)).

 


STM

Joule-Thomson STM
We operate a  JT-STM from SPECS based on the design of Prof. W. Wulfhekel. The cryostat concept is based on a Joule-Thomson stage below a LHe bath cryostat with vapor-cooled shields and a surrounding LNvessel, all in a UHV environment.
Key features:

  • Base temperature: Approximately 1.2 K
  • LHe hold time: >100 hours
  • LN2 time: >80 hours
  • Nanonis control system

 

Réalisation : Sur Mesure concept