We show theoretically that spin and orbital degrees of freedom in the pyrochlore oxide Y2Mo2O7, which is free of quenched disorder, can exhibit a simultaneous glass transition, working as dynamical randomness to each other. The interplay of spins and orbitals is mediated by the Jahn-Teller lattice distortion that selects the choice of orbitals, which then generates variant spin exchange interactions ranging from ferromagnetic to antiferromagnetic ones. Our Monte Carlo simulations detect the power-law divergence of the relaxation times and the negative divergence of both the magnetic and dielectric non-linear susceptibilities, resolving the long-standing puzzle on the origin of the disorder-free spin glass.
@article{arxiv.1908.05070,
title = {Spin-orbital glass transition in a model of a frustrated pyrochlore magnet without quenched disorder},
author = {Kota Mitsumoto and Chisa Hotta and Hajime Yoshino},
journal= {arXiv preprint arXiv:1908.05070},
year = {2020}
}