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Melting of Quasi-Two-Dimensional Charge Stripes in La5/3Sr1/3NiO4

S. -H. Lee·S-W. Cheong
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Abstract

Commensurability effects for nickelates have been studied by the first neutron experiments on La5/3Sr1/3NiO4. Upon cooling, this system undergoes three successive phase transitions associated with quasi-two-dimensional (2D) commensurate charge and spin stripe ordering in the NiO$_2$ planes. The two lower temperature phases (denoted as phase II and III) are stripe lattice states with quasi-long-range in-plane charge correlation. When the lattice of 2D charge stripes melts, it goes through an intermediate glass state (phase I) before becoming a disordered liquid state. This glass state shows short-range charge order without spin order, and may be called a "stripe glass" which resembles the hexatic/nematic state in 2D melting.

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S. -H. Lee, S-W. Cheong. 1997-06-11. Melting of Quasi-Two-Dimensional Charge Stripes in La5/3Sr1/3NiO4. https://doi.org/10.1103/physrevlett.79.2514

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