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arXiv · 1903.04173

Tomonaga-Luttinger liquid spin dynamics in the quasi-one dimensional Ising-like antiferromagnet BaCo$_2$V$_2$O$_8$

Quentin Faure·Shintaro Takayoshi·Virginie Simonet·Béatrice Grenier·Martin Månsson·Jonathan S. White·Gregory S. Tucker·Christian Rüegg·Pascal Lejay·Thierry Giamarchi·Sylvain Petit
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Abstract

Combining inelastic neutron scattering and numerical simulations, we study the quasi-one dimensional Ising anisotropic quantum antiferromagnet \bacovo\ in a longitudinal magnetic field. This material shows a quantum phase transition from a N\'eel ordered phase at zero field to a longitudinal incommensurate spin density wave at a critical magnetic field of 3.8 T. Concomitantly the excitation gap almost closes and a fundamental reconfiguration of the spin dynamics occurs. These experimental results are well described by the universal Tomonaga-Luttinger liquid theory developed for interacting spinless fermions in one dimension. We especially observe the rise of mainly longitudinal excitations, a hallmark of the unconventional low-field regime in Ising-like quantum antiferromagnet chains.

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Quentin Faure, Shintaro Takayoshi, Virginie Simonet, Béatrice Grenier, Martin Månsson, Jonathan S. White, Gregory S. Tucker, Christian Rüegg, Pascal Lejay, Thierry Giamarchi, Sylvain Petit. 2019-03-11. Tomonaga-Luttinger liquid spin dynamics in the quasi-one dimensional Ising-like antiferromagnet BaCo$_2$V$_2$O$_8$. https://doi.org/10.1103/physrevlett.123.027204

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