An Electron Spin Resonance Selection Rule for Spin-Gapped Systems

Abstract

The direct electron spin resonance (ESR) absorption between a singlet ground state and the triplet excited states of spin gap systems is investigated. Such an absorption, which is forbidden by the conservation of the total spin quantum number in isotropic Hamiltonians, is allowed by the Dzyaloshinskii-Moriya interaction. We show a selection rule in the presence of this interaction, using the exact numerical diagonalization of the finite cluster of the quasi-one-dimensional bond-alternating spin system. The selection rule is also modified into a suitable form in order to interpret recent experimental results on CuGeO${}_3$ and NaV${}_2$O${}_5$.

5 pages, Revtex, with 6 eps figures, to appear in J. Phys. Soc. Jpn. Vol. 69 No. 11 (2000)

References in corpus (2)

• Submillimeter Wave ESR Study of Spin Gap Excitations in CuGeO3
• Minimal model to describe the magnetism of $CuGe{O}_3$

Cited by in corpus (12)

• ESR study on the excited state energy spectrum of SrCu${}_2$(BO${}_3$)${}_2$ -a central role of multiple-triplet bound states
• Electron spin resonance in S=1/2 antiferromagnets at high temperature
• Low energy excitations and dynamic Dzyaloshinskii-Moriya interaction in ${\alpha }^{\prime }$-NaV${}_2$O${}_5$ studied by far infrared spectroscopy
• High-field spectroscopy of singlet-triplet transitions in the spin-dimer systems Sr3Cr2O8 and Ba3Cr2O8
• Singlet-triplet excitations and high-field magnetization in CuTe2O5
• Theory of phonon-assisted "forbidden" optical transitions in spin-gapped systems
• Magnetic excitations in the spin-1/2 triangular-lattice antiferromagnet Cs${}_2$CuBr${}_4$
• High-field ESR studies of the quantum spin magnet CaCu2O3
• First ESR Detection of Higgs Amplitude Mode and Analysis with Extended Spin-Wave Theory in Dimer System KCuCl${}_3$
• Coherent two-dimensional THz magnetic resonance spectroscopies for molecular magnets: Analysis of Dzyaloshinskii-Moriya interaction
• Triplons, triplon pairs and dynamical symmetries in laser-driven Shastry-Sutherland magnets
• General structure factor and dynamic effects of the Dzyaloshinskii-Moriya interaction in S = 1/2 clusters