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arXiv · 1306.4216

Spectrum of a magnetized strong-leg quantum spin ladder

D. Schmidiger·P. Bouillot·T. Guidi·R. Bewley·C. Kollath·T. Giamarchi·A. Zheludev
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Abstract

Inelastic neutron scattering is used to measure the spin excitation spectrum of the Heisenberg $S=1/2$ ladder material (C$_7$H$_10$N)$_2$CuBr$_4$ in its entirety, both in the gapped spin-liquid and the magnetic field induced Tomonaga-Luttinger spin liquid regimes. A fundamental change of the spin dynamics is observed between these two regimes. DMRG calculations quantitatively reproduce and help understand the observed commensurate and incommensurate excitations. The results validate long-standing quantum field theoretical predictions, but also test the limits of that approach.

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D. Schmidiger, P. Bouillot, T. Guidi, R. Bewley, C. Kollath, T. Giamarchi, A. Zheludev. 2013-06-18. Spectrum of a magnetized strong-leg quantum spin ladder. https://doi.org/10.1103/physrevlett.111.107202

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