Functional Materials for Energy
Magnetic spin waves (i.e., magnons), were discovered to move very quickly along only one direction in the intermetallic compound CrSb2. This is surprising, since more isotropic magnetism was expected from the dense three-dimensional marcasite crystal structure. Because magnons can carry heat, these results suggest that the thermal conductivity of CrSb2 will also be anisotropic. This was indeed found to be the case with more heat conduction along the direction of high magnon velocity. This exciting result suggests a novel route for designing materials that conduct heat well in one direction but poorly in the other two. Such a material would be of interest in many thermal management applications where heat needs to be guided in one direction. This research was made possible by a broad collaboration involving experts in materials synthesis, first principles theory, and both reactor based and spallation-source based inelastic neutron scattering measurements.
For more information, please contact Matthew Stone, stonemb@ornl.gov.
M. B. Stone, M. D. Lumsden, S. E. Nagler, D. J. Singh, J. He, B. C. Sales and D. Mandrus, “Quasi-One-Dimensional Magnons in an Intermetallic Marcasite," Phys. Rev. Lett. 108, 167202 (2012). (DOI:10.1103/PhysRevLett.108.167202).