PARADIM Highlight #97—External User Research (2024)—External User Project (2024)
Samaresh Guchhait (Howard University) and collaborators
The discovery of intrinsic magnetism in atomically thin sheets of chromium iodine (CrI3) fuels the search for related layered materials, to gain a better understanding in the emergence of magnetic properties and to find new candidates for future applications ranging from sensors and data storage to refrigeration.
Figure 1: (Top) Three-dimensional and polyhedral views of the refined crystallographic unit cell and Laue diffraction image of the single-crystal Cr2Te3 sample. (bottom) Scaling of change of magnetic entropy curves: −ΔSM/H(1−α)/Δvs ε/H1/Δ along the (a) c-axis and (b) ab-plane.
Here, users of PARADIM explored the rich phase space of chromium and tellurium (Cr, Te). The CrTe2 endmember is a layered dichalcogenide, with a series of interstitially ordered Cr rich phases, Cr2+xTe4. Using PARADIM’s capabilities in single crystal growth, the group realized CrTe2, Cr1.27Te2, Cr2Te3, and Cr3Te4 and subsequently characterized the materials properties, reported across several works.
Cr2Te3 is found to have a large, and highly anisotropic magnetocaloric effect at its magnetic phase transition temperature of T = 170 K. Since it is known that the magnetic ordering temperature increases to T = 280 K in the thin film limit, the PARADIM users conclude that Cr2Te3, with further chemical tuning, holds great promise as a thin film, room temperature, magnetocaloric for integration into electronic and solid-state devices.
PARADIM users selectively prepared single crystals of ordered interstitial compositions in the Cr2+xTe4 phase space, enabling study of the individual magnetic properties as a function of the number and distribution of interstitial Cr ions. Cr2Te3 is found to have a large, and highly anisotropic magnetocaloric effect at its magnetic phase transition temperature of T = 170 K. Since it is known that the magnetic ordering temperature increases to T = 280 K in the thin film limit, the PARADIM users conclude that Cr2Te3, with further chemical tuning, holds great promise as a thin film, room temperature, magnetocaloric for integration into electronic and solid state devices.
Few materials that remain magnetic when taken to the few layer limit are known, and fewer still are known to have a large magnetocaloric effect. By precisely controlling the chemical composition and interstitial ordering, the users found that Cr2Te3 has a large magnetocaloric effect that make it potentially useful for novel forms of refrigeration and sensing in thin film form.
PARADIMs CVD growth of high-quality, compositionally precise Cr2+xTe4.
The work was initialized by Prof. Guchhait from Howard University.
- A. Goswami, N. Ng, E. Yakubu, A.M. Milinda Abeykoon, and S. Guchhait, "Critical Behavior in Monoclinic Cr3Te4," Phys. Rev. B 109, 054413 (2024). DOI: https://doi.org/10.1103/PhysRevB.109.054413
- A. Goswami, N. Ng, A.M. Milinda Abeykoon, E. Yakubu, and S. Guchhait, "High Magnetic Anisotropy and Magnetocaloric Effects in Single Crystal Cr2Te3," ACS Appl. Electron. Mater. 6, 4043–4056 (2024). DOI: https://doi.org/10.1021/acsaelm.4c00009
- A. Goswami, N. Ng, E. Yakubu, G. Bassen, and S. Guchhait, "Quasi-2D-Ising-Type Magnetic Critical Behavior in Trigonal Cr1.27Te2," J. Chem. Phys. 160, 214704 (2024). DOI: https://doi.org/10.1063/5.0208764
- A. Goswami, N. Ng, E. Yakubu, S. Guchhait, “Room temperature mangetocaloric effects in monoclinic Cr3Te4,” J. Appl. Phys. 137, 043909 (2025). DOI: https://doi.org/10.1063/5.0234906
- This work is supported by the National Science Foundation Awards No. DMR-2018579 and No. DMR-2302436. This work made use of the synthesis facility of the Platform for the Accelerated Realization, Analysis, and Discovery of Interface Materials (PARADIM), which is supported by the National Science Foundation under Cooperative Agreement No. DMR-2039380. This research used beamline 28-ID-1 of the National Synchrotron Light Source-II, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No. DE-SC0012704. The authors are grateful to Professor Raymond Orbach of the University of Texas at Austin and Dr. John Tranquada of Brookhaven National Laboratory for thoughtful discussions.
- This work is supported by the National Science Foundation Awards No. DMR-2018579 and No. DMR-2302436. This work made use of the synthesis facility of the Platform for the Accelerated Realization, Analysis, and Discovery of Interface Materials (PARADIM), which is supported by the National Science Foundation under Cooperative Agreement No. DMR-2039380. This research used beamline 28-ID-1 of the National Synchrotron Light Source-II, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No. DE-SC0012704.
- This work was supported by the National Science Foundation under Award Nos. DMR-2018579 and DMR-2302436. This work made use of the synthesis facility of the Platform for the Accelerated Realization, Analysis, and Discovery of Interface Materials (PARADIM), which was supported by the National Science Foundation under Cooperative Agreement No. DMR-2039380. We are thankful to Dr. Maxime Siegler of Johns Hopkins University for SCXRD experiments.
- This work was supported by the National Science Foundation Award Nos. DMR-2018579 and DMR-2302436. This work made use of the synthesis facility of the Platform for the Accelerated Realization, Analysis, and Discovery of Interface Materials (PARADIM), which is supported by the National Science Foundation under Cooperative Agreement No. DMR-2039380. We are thankful to Dr. Pratap Pal for the fruitful discussion in magnetocaloric studies.
