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arXiv · 2006.01239

Evidence for the Alternating Next-Nearest Neighbor model in the dynamic behavior of a frustrated antiferromagnet

Adra Carr·John Bowlan·3·Claudio Mazzoli·Andi Barbour·Wen Hu·Stuart Wilkins·Colby Walker·Xiaxin Ding·Jong Hyuk Kim·Nara Lee·Young Jai Choi·Shi-Zeng Lin·Richard L. Sandberg·Vivien S. Zapf
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Abstract

X-ray photon correlation spectroscopy (XPCS) enables us to study dynamics of antiferromagnets. Using coherent soft X-ray diffraction, we resonantly probe Mn and Co Bragg peaks in the frustrated magnetic chain compound Lu2CoMnO6 significantly below the Neel temperature. Bragg peaks of incommensurate order slide towards commensurate 'up up down down' order with decreasing temperature. Antiferromagnetic inhomogeneities produce speckle within the Bragg peaks, whose dynamics are probed by XPCS and compared to the classic Axial Next-Nearest Neighbor Interaction model of frustration. The data supports a novel model prediction: with decreasing temperature the dynamics become faster.

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Adra Carr, John Bowlan, 3, Claudio Mazzoli, Andi Barbour, Wen Hu, Stuart Wilkins, Colby Walker, Xiaxin Ding, Jong Hyuk Kim, Nara Lee, Young Jai Choi, Shi-Zeng Lin, Richard L. Sandberg, Vivien S. Zapf. 2020-06-01. Evidence for the Alternating Next-Nearest Neighbor model in the dynamic behavior of a frustrated antiferromagnet. https://doi.org/10.1103/physrevb.103.l060401

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