The pyrovanadate alpha-Cu2V2O7 belongs to the orthorhombic (Fdd2) class of crystals with noncentrosymmetric crystal structure. Recently, the compound has been identified to be a magnetic multiferroic with a substantial electric polarization below the magnetic transition temperature TC = 35 K. Here we report the results of our inelastic neutron scattering (INS) studies on a polycrystalline sample of alpha-Cu2V2O7. Our INS data clearly show the existence of dispersive spin wave excitations below TC with a zone-boundary energy of 11 meV at 5 K.We have analyzed the data using linear spin wave theory, which shows good agreement between the experiment and calculation. The analysis is consistent with the third nearest neighbor exchange interaction playing a dominant role in the magnetism of the material.
@article{arxiv.1610.03969,
title = {Spin wave excitations in the pyrovanadate alpha-Cu2V2O7},
author = {A. Banerjee and J. Sannigrahi and S. Bhowal and I. Dasgupta and S. Majumdar and H. C. Walker and A. Bhattacharyya and D. T. Adroja},
journal= {arXiv preprint arXiv:1610.03969},
year = {2016}
}