Ex-Situ Characterization

Some measurements can only be performed after our deposited materials have been turned into devices in the UCSB NanoFab. Others are only possible in separate systems. Some ex-situ measurements can be performed in-house, but we extensively use the shared-use CNSI and NanoFab facilities as well. 

PPMS
PPMS

Quantum Design Physical Property Measurement System (PPMS)

  • Extremely customizable I-V and C-V measurements made at variable temperature from 1.9 K up to 400 K  and variable magnetic field up to 14 T in AC or DC configuration
  • Includes a 3He insert for 500 mK measurements
  • Allows study of Hall effect for carrier concentrations, effective mass, topological properties such as chiral pumping, and more
MPMS
MPMS

Quantum Design Magnetic Property Measurement System (MPMS SQUID Magnetometer)

  • High resolution magnetic measurements down to 1.8 K and up to 7 T
  • Full suite of magnetic measurements with ≤10-8 emu sensitivity

Low temperature Photoluminescence

  • Excitation source of 980 nm and 532 nm lasers with sample cooling down to ~25 K
  • Gives accurate measurements of quality of semiconductors studied
  • More detailed studies give information on localized impurity/defect states, excitons, and other optically active states
ADR
ADR

HPD Adiabatic Demagnetization Refrigerator (ADR)

  • Cyclic demagnetization of a paramagnet absorbs entropy from thermal vibrations and pumps it into a LHe working fluid
  • Transport measurements can be performed down to 100 mK using a 5 T superconducting magnet
Mock-up of the suitcase
Mock-up of the suitcase

Vacuum Suitcases

  • A vacuum suitcase allows samples to be brought to beamlines and other external analysis centers without adding a capping layer
  • Suitcase base pressure less than 1E-10 Torr ensures pristine surfaces on long journeys
  • Current vacuum suitcase in use since 2017 and compatible with MBE/ARPES/STM
  • Three new compact vacuum suitcase (two horizontal, one vertical) in collaboration with the Quantum Foundry