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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 Tm⁢VO4. 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. 

α-RuCl3 is considered to be the top candidate material for the experimental realization of the celebrated Kitaev model, where ground states are quantum spin liquids with interesting fractionalized excitations. It is, however, known that additional interactions beyond the Kitaev model trigger in α-RuCl3 a long-range zigzag antiferromagnetic ground state. In this work, we investigate a nanoflake of α-RuCl3 through guarded high impedance measurements aimed at reaching the regime where the system turns into a zigzag antiferromagnet. We investigated a variety of temperatures (1.45–175 K) and out-of-plane magnetic fields (up to 11 T), finding a clear signature of a structural phase transition at ≈160 K as reported for thin crystals of α-RuCl3, as well as a thermally activated behavior at temperatures above ≈30 K, with a characteristic activation energy significantly smaller than the energy gap that we observe for α-RuCl3 bulk crystals through our angle resolved photoemission spectroscopy (ARPES) experiments. Additionally, we found that below ≈30 K, transport is ruled by Efros–Shklovskii variable range hopping (VRH). Most importantly, our data show that below the magnetic ordering transition known for bulk α-RuCl3 in the frame of the Kitaev–Heisenberg model (≈7 K), there is a clear deviation from VRH or thermal activation transport mechanisms. Our work demonstrates the possibility of reaching, through specialized high impedance measurements, the thrilling ground states predicted for α-RuCl3 at low temperatures in the frame of the Kitaev–Heisenberg model and informs about the transport mechanisms in this material in a wide temperature range.