Synthesis and Magnon Thermal Transport Properties of Spin Ladder Sr₁₄Cu₂₄O₄₁ Microstructures

Abstract

The spin ladder compound (Sr,Ca,La) 14 Cu 24 O 41 exhibits an incommensurate layered structure with strong antiferromagnetic coupling. Besides intriguing superconducting behavior, recent experiments on bulk Sr 14 Cu 24 O 41 single crystals have revealed a remarkable magnon thermal conductivity, which is the largest above 100 K among all known quantum magnets. Although bulk (Sr,Ca,La) 14 Cu 24 O 41 crystals have been synthesized and studied extensively, there have been few reports on the synthesis and magnon thermal transport investigation of their microstructures. Here, we report the synthesis and thermal transport properties of Sr 14 Cu 24 O 41 microrods. Electron microscopy studies indicate that these microrods synthesized by a co-precipitation method are single crystals grown preferentially along the ladder axis. Based on a four-probe thermal transport measurement, the thermal conductivity of the microrods reveals appreciable magnon transport in the microstructures. According to a kinetic model analysis, magnon transport in the microrods is suppressed mainly by increased point defect scattering compared to the bulk crystals, whereas surface scattering is negligible for anisotropic one-dimensionalThis article is protected by copyright. All rights reserved.3 magnon transport along the ladder. Moreover, the thermal conductivity is enhanced after annealing as a result of reduced oxygen vacancies. These results help to build the foundation for future heterogeneous integration of magnetic microstructures in microscale devices for the transport of energy and quantum information.

Spin gap in quasi-one-dimensional S = 3/2 antiferromagnet CoTi2O5

“…7(a), and the parameters are achieved as p = 3.9 × 10 3 K −4 •s −1 , U = 2.3 × 10 7 s −1 , b = 16, which are reasonable for an insulator, [42,43] demonstrating that the low-temperature peak at T * in κ(T ) is the phonon peak and the high-temperature peak in κ(T ) comes from the contribution of magnon. This double-peak behavior was also found in the κ(T ) curve along the spin chain direction in some quasi-1D antiferromagnets, such as Sr 14 Cu 24 O 41 , [44] because the magnetic excitations propagate along the spin chain direction. The magnon thermal conductivity κ m of CoTi 2 O 5 can be obtained by deducting the κ ph from the total thermal conductivity of CoTi 2 O 5 , as shown by the solid line in Fig.…”