Modular portable unit for thermal conductivity measurements in multiple cryogenic/magnetic field environments

Abstract

A modular design for a miniature thermal conductivity cell suitable for a dilution refrigerator and other sample-in-vacuum cryogenic environments with different magnet options is described. The sample is mounted once and the contacts remain in place when the unit is repositioned or transported between different magnets and cryostats. This mobility enables comprehensive measurements with access to specific options, such as vector magnet in one lab and ultra-high field in another. This design enables significant expansion of the temperature range by using not only dilution refrigerators but also He,He cryostats and even ubiquitous Quantum Design Physical Property Measurement System.

Clathrate BaNi2P4: An Interplay of Heat and Charge Transport Due to Strong Host–Guest Interactions

“…Laue diffraction confirmed that the samples were high-quality single crystals ( Figure S6). Thermal conductivity measurements were performed using modular thermal conductivity (MTC) setups, [20] enabling measurements in several cryogenic environments, a cryogen-free He3 setup (0.5 to 3 K) and the high-vacuum option of a PPMS (above 2 K), without sample dismounting. A standard one-heater-two-thermometers technique was used for thermal conductivity measurements.…”

“…The first MTC setup utilized RuO2 thermometers and was constructed for measurements in the temperature range 0.02 to 40 K. The second setup used Cernox 1030 thermometers, suitable for measurements from 0.3 to 300 K. The calibration of the modular thermal conductivity setup with RuO2 thermometers was described elsewhere. [20] The design with Cernox 1030 thermometers was specially built to study the properties of BaNi2P4 at elevated temperatures. This device was tested using measurements of standard Ag wire as shown in the supplementary material ( Figure S4).…”

“…In order to measure both electrical resistivity and thermal conductivity on the same sample without dismounting from the MTC device, the high resistance wire of the thermal conductivity apparatus was temporarily shortened. [20] Use of the same sample in both measurements effectively diminished the uncertainty of geometric factor determinations in the two measurements. [20] Magnetization measurements in the 1.8 -300 K temperature range were performed using the VSM option of a Quantum Design Magnetic Property Measurement System (MPMS3).…”

“…[20] Use of the same sample in both measurements effectively diminished the uncertainty of geometric factor determinations in the two measurements. [20] Magnetization measurements in the 1.8 -300 K temperature range were performed using the VSM option of a Quantum Design Magnetic Property Measurement System (MPMS3). The sample was mounted on a quartz sample holder that has virtually no background.…”

Point-node gap structure of the spin-triplet superconductor UTe2

“…Contacts for thermal transport measurements were made by soldering gold wire leads to evaporated gold pads using an In-Sn alloy, resulting in ∼mΩ contact resistances. Thermal transport was measured in a dilution refrigerator (DR) using a modular one-heater, two-thermometer probe [10], and heat capacity measured using the relaxation time method. As discussed below, the observation of the WF law in the field-induced normal state rules out electron-phonon decoupling issues [11].…”