Temperature dependent 89Y NMR study on multiferroic YCrO3

In this manuscript, we report the Y-89 NMR measurement as a function of temperature on single phase and pure polycrystalline YCrO3 sample to study the magnetism and relaxation times on a microscopic level across the magnetic transition (T-N similar or equal to 141 K) from paramagnetic to antiferromagnetic state. The NMR peak width broadens abruptly upon crossing T-N due to the onset of internal magnetic fields, while peakshift slight decreases. A slight increase and subsequent anomalous decrease in the NMR peak intensity is observed on approaching T-N from 300 K. There is also a significant increase in peak width. The temperature dependence of the Y-89 NMR spin-lattice relaxation rates 1/T-1 indicates a phase transition at T-N which is of magnetic origin due to Cr3+ ions, with an anomalously rise of fluctuations below T-N. Above T-N, this spin-lattice relaxation rate can be fitted to a power-law scaling behavior 1/T-1 similar to T-beta with an exponent factor beta approximate to 0.8, indicates low energy spin fluctuations. Moreover, Knight shift and 1/TT1 scales linear with the bulk susceptibility which suggests the antiferromagnetic spin fluctuation in the YCrO3 system.

Automated summary

This manuscript reports Y-89 NMR measurements on single phase and pure polycrystalline YCrO3 samples to study magnetism and relaxation times during the magnetic transition from paramagnetic to antiferromagnetic state. The results show abrupt broadening of NMR peak width and slight decrease in peakshift at T-N, followed by a slight increase and subsequent anomalous decrease in NMR peak intensity. The Y-89 NMR spin-lattice relaxation rates indicate a magnetic phase transition at T-N, with fluctuations below T-N and low energy spin fluctuations above T-N. Additionally, Knight shift and 1/T1T scale linearly with bulk susceptibility, suggesting antiferromagnetic spin fluctuations in the YCrO3 system.