Giant elastocaloric effect at low temperatures in TmVO4 and implications for cryogenic cooling

• 成果类型: Article
• 署名作者: Zic, Mark P.; Ikeda, Matthias S.; Massat, Pierre; Hollister, Patrick M.; Ye, Linda; Rosenberg, Elliott W.; Straquadine, Joshua A. W.; Li, Yuntian; Ramshaw, B. J.; Fisher, Ian R.
• 署名单位: Stanford University; Stanford University; Stanford University; Cornell University; Cornell University; Canadian Institute for Advanced Research (CIFAR)
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-12815
• DOI: 10.1073/pnas.2320052121
• 发表日期: 2024-06-18
• 关键词: pressure

摘要

Adiabatic decompression of paraquadrupolar materials has significant potential as a cryogenic cooling technology. We focus on TmVO 4 , 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 k B ln 2 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 4 , 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.