Repulsively bound magnon excitations of a spin-1/2 XXZ chain in a staggered transverse field

Abstract

We study the excitation spectrum of the one-dimensional spin-1/2 XXZ chain with antiferromagnetic Ising anisotropy across a magnetic quantum phase transition induced by the application of a site-dependent transverse magnetic field. Motivated by the chain antiferromagnet BaCo${}_2$V${}_2$O${}_8$, we consider a situation where the transverse magnetic field has a strong uniform component and a weaker staggered part. To determine the nature of the excitations giving rise to the spin dynamical structure factor, we use a combination of analytical approaches and the numerically exact time-dependent matrix product state method. We identify below the quantum phase transition high-energy many-body two-magnon and three-magnon repulsively bound states which are clearly visible due to the staggered component of the magnetic field. At high magnetic fields and low temperature, single magnons dominate the dynamics. Our theory results are in very good agreement with terahertz spectroscopy experimental results presented in [Wang et al., Nature 631, 760 (2024)].

References in corpus (15)

• The density-matrix renormalization group in the age of matrix product states
• Real time evolution using the density matrix renormalization group
• The ITensor Software Library for Tensor Network Calculations
• Bose-Einstein Condensation in Magnetic Insulators
• Repulsively bound atom pairs in an optical lattice
• New Trends in Density Matrix Renormalization
• Fractional excitations in the square-lattice quantum antiferromagnet
• Controlling Luttinger liquid physics in spin ladders under a magnetic field
• Direct Observation of Magnon Fractionalization in the Quantum Spin Ladder
• Novel ordering of an S = 1/2 quasi one-dimensional Ising-like anitiferromagnet in magnetic field
• Quantum criticality in the spin-$1/2$ Heisenberg chain system copper pyrazine dinitrate
• Tomonaga-Luttinger liquid spin dynamics in the quasi-one dimensional Ising-like antiferromagnet BaCo${}_2$V${}_2$O${}_8$
• Finite-temperature correlations in a quantum spin chain near saturation
• Dynamics and symmetries of a repulsively bound atom pair in an infinite optical lattice
• Phase transitions and spin dynamics of the quasi-one dimensional Ising-like antiferromagnet BaCo${}_2$V${}_2$O${}_8$ in a longitudinal magnetic field

Cited by in corpus (3)

• Experimental observation of repulsively bound magnons
• 1/5 and 1/3 magnetization plateaux in the spin 1/2 chain system YbAlO3
• Confinement of spinons in the XXZ spin-1/2 chain in presence of the transverse magnetic field