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arXiv · 1803.05597

Tuning a random field mechanism in a frustrated magnet

Shashikant Singh Kunwar·Arnab Sen·Thomas Vojta·Rajesh Narayanan
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Abstract

We study the influence of spinless impurities on a frustrated magnet featuring a spin-density wave (stripe) phase by means of Monte Carlo simulations. We demonstrate that the interplay between the impurities and an order parameter that breaks a real-space symmetry triggers the emergence of a random-field mechanism which destroys the stripe-ordered phase. Importantly, the strength of the emerging random fields can be tuned by the repulsion between the impurity atoms; they vanish for perfect anticorrelations between neighboring impurities. This provides a novel way of controlling the phase diagram of a many-particle system. In addition, we also investigate the effects of the impurities on the character of the phase transitions between the stripe-ordered, ferromagnetic, and paramagnetic phases.

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cond-mat.dis-nncond-mat.stat-mechcond-mat.str-el

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Shashikant Singh Kunwar, Arnab Sen, Thomas Vojta, Rajesh Narayanan. 2018-03-15. Tuning a random field mechanism in a frustrated magnet. https://doi.org/10.1103/physrevb.98.024206

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