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Adiabatic decompression of paraquadrupolar materials has significant potential as a cryogenic cooling technology. We focus on TmVO , an archetypal material that undergoes a continuous phase transition to a ferroquadrupole-ordered state at 2.15 K. Above the phase transition, each Tm ion contributes an entropy of due to the degeneracy of the crystal electric field groundstate. Owing to the large magnetoelastic coupling, which is a prerequisite for a material to undergo a phase transition via the cooperative Jahn–Teller effect, this level splitting, and hence the entropy, can be readily tuned by externally induced strain. Using a dynamic technique in which the strain is rapidly oscillated, we measure the adiabatic elastocaloric response of single-crystal TmVO , and thus experimentally obtain the entropy landscape as a function of strain and temperature. The measurement confirms the suitability of this class of materials for cryogenic cooling applications and provides insight into the dynamic quadrupole strain susceptibility.
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This content will become publicly available on January 1, 2026
Giant elastocaloric cooling at cryogenic temperatures in TmVO4 via a load-unload strain technique
The adiabatic elastocaloric effect relates changes in the strain that a material experiences to resulting changes in its temperature. While elastocaloric materials have been utilized for cooling in room-temperature applications, the use of such materials for cryogenic cooling remains relatively unexplored. Here, we use a strain load-unload technique at low temperatures, similar to those employed at room temperature, to demonstrate a large cooling effect in TmVO4. For strain changes of 1.8 ×10−3, the inferred cooling reaches approximately 50% of the material’s starting temperature at 5 K, justifying the moniker “giant.” Beyond establishing the suitability of this class of material for cryogenic elastocaloric cooling, these measurements also provide additional insight into the entropy landscape in the material as a function of strain and temperature, including the behavior proximate to the quadrupolar phase transition.
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- Award ID(s):
- 2232515
- PAR ID:
- 10577416
- Publisher / Repository:
- American Physical Society
- Date Published:
- Journal Name:
- Physical Review Applied
- Volume:
- 23
- Issue:
- 1
- ISSN:
- 2331-7019
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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