Magnetic excitation spectrum and Hamiltonian of the quantum spin chain BaCuTe2O6

Abstract

The magnetic excitation spectrum and Hamiltonian of the quantum magnet BaCuTe2O6 is studied by inelastic neutron scattering (INS) and density functional theory (DFT). INS on powder and single crystal samples reveals overlapping spinon continuua - the spectrum of an antiferromagnetic spin-1/2 spin chain - due to equivalent chains running along the a, b, and c directions. Long-range magnetic order onsets below TN = 6.3 K due to interchain interactions, and is accompanied by the emergence of sharp spin-wave excitations which replace the continuua at low energies. The spin-wave spectrum is highly complex and was successfully modelled achieving excellent agreement with the data. The extracted interactions reveal an intrachain interaction, J3 = 2.9 meV, while the antiferromagnetic hyperkagome interaction J2, is the sub-leading interaction responsible for coupling the chains together in a frustrated way. DFT calculations reveal a similar picture for BaCuTe2O6 of dominant J3 and sub-leading J2 antiferromagnetic interactions and also indicate a high sensitivity of the interactions to small changes of structure which could explain the very different Hamiltonians observed in the sister compounds SrCuTe2O6 and PbCuTe2O6.

12 pages, 8 figures

References in corpus (10)

• Magnetic properties and heat capacity of the three-dimensional frustrated S=1/2 antiferromagnet PbCuTe2O6
• Fate of partial order on the trillium and distorted windmill lattices
• Theoretical study of quantum spin liquids in $S=1/2$ hyper-hyperkagome magnets: classification, heat capacity, and dynamical spin structure factor
• Classical and quantum order in hyperkagome antiferromagnets
• Low-dimensional magnetism of BaCuTe${}_2$O${}_6$
• Magnetic properties and magnetic structure of the frustrated quasi-one-dimensional antiferromagnet SrCuTe${}_2$O${}_6$
• Magnetic structure of a new quantum magnet SrCuTe${}_2$O${}_6$
• Structural and magnetic properties of the new quantum magnet BaCuTe${}_2$O${}_6$
• Crystal growth, characterization and phase transition of PbCuTe${}_2$O${}_6$
• Weak three-dimensional coupling of Heisenberg quantum spin chains in SrCuTe${}_2$O${}_6$

Cited by in corpus (1)

• Fragile spin liquid in three dimensions