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arXiv · 2007.02972

Triplons, Magnons, and Spinons in a Single Quantum Spin System: SeCuO3

Luc Testa·Vinko Surija·Krunoslav Prsa·Paul Steffens·Martin Boehm·Philippe Bourges·Helmut Berger·Bruce Normand·Henrik Ronnow·Ivica Zivkovic
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Abstract

Quantum spin systems exhibit an enormous range of collective excitations, but their spin waves, gapped triplons, fractional spinons, or yet other modes are generally held to be mutually exclusive. Here we show by neutron spectroscopy on SeCuO$_3$ that magnons, triplons, and spinons are present simultaneously. We demonstrate that this is a consequence of a structure consisting of two coupled subsystems and identify all the interactions of a minimal magnetic model. Our results serve qualitatively to open the field of multi-excitation spin systems and quantitatively to constrain the complete theoretical description of one member of this class of materials.

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Luc Testa, Vinko Surija, Krunoslav Prsa, Paul Steffens, Martin Boehm, Philippe Bourges, Helmut Berger, Bruce Normand, Henrik Ronnow, Ivica Zivkovic. 2020-07-06. Triplons, Magnons, and Spinons in a Single Quantum Spin System: SeCuO3. https://doi.org/10.1103/physrevb.103.l020409

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