Transport labs

Materials with strong interactions in their interfaces and structural phase transitions are potential building blocks for functional intelligent materials. Such correlated electronic phenomenon give rise to novel underlying physics such as quantum hall effect, valley transport, topological phenomenon, unconventional magnetic ordering etc, many of which reveal themselves in electrical resistance measurements at elevated magnetic fields and ultra-low temperatures. The transport labs in I-FIM will continually be equipped with versatile cryogenic facilities that can perform such magnetotransport measurement with minimal user intervention. Each lab has been built with a separate support room to house the compressors, pumping and gas handling systems to minimize the transmitted mechanical vibration from these sources. Availability of cryostats with unique field strengths and base temperatures in I-FIM’s experimental repertoire strongly enhance our capabilities to pursue multiple projects simultaneously, with a high turnaround time. Crucially, the sample holders in the transport cryostats are compatible with the optical cryostats, to enable researchers to perform these complementary measurements in tandem and realize deliverables quickly. Going forward, plans are in place to obtain specialized apparatus for performing magnetotransport experiments in the milliKelvin range and in the presence of electromagnetic radiation spanning across the sub-THz to visible frequency domains. 

List No. 

Key specifications for existing equipment 

Picture 

A. Cryostat 1 

  • Cryogen free closed-loop variable temperature insert (VTI) with a Helium3 sample probe. Extensively used to study moiré superlattices in twisted 2D materials 
  • Allows quick sample exchange (top loading insert)  
  • Superconducting Magnet ±8 Tesla (vertical) 
  • 2 Sample inserts: 1. Helium3 (Base-Temperature 300 milliKelvin), 2. Rotator head (Base-Temperature 1.5 Kelvin) 
    • Cooldown time <12 hours 
    • LCC44 chip carrier  
    • Rotator probe allows automated rotation with range 180° (x-axis), 90° (y-axis) and 360° (z-axis) 
B. Cryostat 2 and 3 

Cryogen free closed-loop VTI’s, each with its own Helium3 insert. 

    • Allows quick sample exchange (top loading inserts)  
    • Superconducting Magnet ±14 Tesla (vertical) and ±16 Tesla (vertical) 
    • 2 Sample inserts: 1. Helium3 (Base-Temperature 300 milliKelvin), 2. Rotator head (Base-Temperature 1.5 Kelvin) 
    • Cooldown time <12 hours 
    • In addition to DC lines, the 2 Helium3 probes are fitted with SS semi-rigid coaxial cables for high frequency experiments 
    • LCC44 chip carrier  
    • Rotator probe allows automated rotation with range 360° (z-axis) 
C Cryostat 4

A cryogen free state-of-the-art Blufors dilution refrigerator:

  • Bottom loader with motorized sample loader on load lock for fast sample exchange
  • Base temperature of <10 milliKelvin (without thermal load)
  • Superconducting magnet ±12 Tesla (vertical)
  • Supreme vibration isolation from environment and the pulse tube
  • Piezo based sample rotator (Model: Atto3DR) that allows full 3D sphere via ±90° via closed loop rotation (reserve: ±10°)
  • QBoard- PCB-based sample holder system for low-temperature spin-qubit chips, general transport experiments, and superconducting circuits. Complemented with ultra-low noise measurement and signal processing electronics from QDevil
  • Cryogenic filters ensure ultra-low electron temperature.