Magnetodipolar interaction and quasiparticles delocalization in disordered quantum magnets

Abstract

It is well-known that disordered quantum magnets usually host localized elementary excitations in gapped phases. Here we show that long-range magnetodipolar interaction can lead to quasiparticles delocalization in the three-dimensional case, similarly to the phenomenon previously described for localized vibrational modes in disordered solids. Employing renormalization group-like ideas, the average eigenmode occupation number is found to scale with the system size, which also leads to sub-diffusive dynamical properties of the system.

4 pages, 1 figure

References in corpus (5)

• Bose-Einstein Condensation in Magnetic Insulators
• Localized and propagating excitations in gapped phases of spin systems with bond disorder
• Theory of field-induced quantum phase transition in spin dimer system Ba${}_3$Cr${}_2$O${}_8$
• Self-consistent T-matrix approach to gap renormalization in quantum magnets with bond disorder
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