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arXiv · 2104.07890

Spin-ice dynamics of pyrochlore Dy2GaSbO7 with enhanced Pauling zero-point entropy

Saikat Nandi·Yatramohan Jana·Jahangir Alam·Pallab Bag·S. S. Islam·Ramesh Nath
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Abstract

We report the low-temperature magnetothermal properties and spin dynamics of a mixed pyrochlore, Dy2GaSbO7 through the coordination of measurements of dc magnetization, ac susceptibility, and heat capacity, and CF computation. In Dy2GaSbO7, the spins freeze at temperature Tice = 3.1 K, corresponding to dynamical spin-freezing into a disordered state in compliance with the spin-ice rules, but with enhanced zero-point entropy, unlike cannonical dipolar spin-ice materials, Dy2Ti2O7 and Ho2Ti2O7, due to random disorder and varied chemical pressure of B-site (GaSb tetrahedra) ions.

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Saikat Nandi, Yatramohan Jana, Jahangir Alam, Pallab Bag, S. S. Islam, Ramesh Nath. 2021-04-16. Spin-ice dynamics of pyrochlore Dy2GaSbO7 with enhanced Pauling zero-point entropy. https://arxiv.org/abs/2104.07890

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