We have synthesized single crystalline sample of Mn2V2O7 using floating zone technique and investigated the ground state using magnetic susceptibility, heat capacity and neutron diffraction. Our magnetic susceptibility and heat capacity reveal two successive magnetic transitions at TN1= 19 K and TN2= 11.8 K indicating two distinct magnetically ordered phases. The single crystal neutron diffraction study shows that in the temperature (T) range 11.8 K ≤T≤ 19 K the magnetic structure is commensurate with propagation vector k1=(0,0.5,0), while upon lowering temperature below TN2= 11.8 K an incommensurate magnetic order emerges with k2=(0.38,0.48,0.5) and the magnetic structure can be represented by cycloidal modulation of the Mn spin in ac−plane. We are reporting this commensurate to incommensurate transition for the first time. We discuss the role of the magnetic exchange interactions and spin-orbital coupling on the stability of the observed magnetic phase transitions.
@article{arxiv.1905.08722,
title = {Commensurate to incommensurate magnetic phase transition in Honeycomb-lattice pyrovanadate Mn2V2O7},
author = {J. Sannigrahi and D. T. Adroja and R. Perry and M. J. Gutmann and V. Petricek and D. Khalyavin},
journal= {arXiv preprint arXiv:1905.08722},
year = {2019}
}