Noninteger-spin magnonic excitations in untextured magnets

Abstract

Interactions are responsible for intriguing physics, e.g. emergence of exotic ground states and excitations, in a wide range of systems. Here we theoretically demonstrate that dipole-dipole interaction leads to bosonic eigen-excitations with average spin ranging from zero to above $\hslash$ in magnets with uniformly magnetized ground states. These exotic excitations can be interpreted as quantum coherent conglomerates of spin $\hslash$ magnons, the eigen-excitations when the dipolar interactions are disregarded. We further find that the eigenmodes in an easy-axis antiferromagnet are spin-zero quasiparticles instead of the widely believed spin $\pm \hslash$ magnons. The latter re-emerge when the symmetry is broken by a sufficiently large applied magnetic field. The average spin greater than $\hslash$ is accompanied by vacuum fluctuations and may be considered to be a weak form of frustration.

5 pages, 3 figures, Supplementary material

References in corpus (7)

• Dirac Strings and Magnetic Monopoles in Spin Ice Dy2Ti2O7
• Spin pumping and spin-transfer torques in antiferromagnets
• Thermal spin dynamics of yttrium iron garnet
• Observation of Magnetic Monopoles in Spin Ice
• Spin Seebeck effect in antiferromagnets and compensated ferrimagnets
• Spin pumping and shot noise in ferrimagnets: bridging ferro- and antiferromagnets
• Thermally induced magnon accumulation in two-sublattice magnets

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