Spinel compounds are of great interest in both fundamental and application-oriented perspectives due to the geometric magnetic frustration inherent to their lattice and the resulting complex magnetic states.Here,we ap...Spinel compounds are of great interest in both fundamental and application-oriented perspectives due to the geometric magnetic frustration inherent to their lattice and the resulting complex magnetic states.Here,we applied x-ray diffraction,magnetization,heat capacity and powder inelastic neutron scattering measurements,along with theoretical calculations,to study the exotic properties of chromite-spinel oxides CoCr_(2)O_(4) and MnCr_(2)O_(4).The temperature dependence of the phonon spectra provides an insight into the correlation between oxygen motion and the magnetic order,as well as the magnetoelectric effect in the ground state of MnCr_(2)O_(4).Moreover,spin-wave excitations in CoCr_(2)O_(4) and MnCr_(2)O_(4) are compared with Heisenberg model calculations.This approach enables the precise determination of exchange energies and offers a comprehensive understanding of the spin dynamics and relevant exchange interactions in complicated spiral spin ordering.展开更多
基金the financial support from the National Key Research and Development Program of China(Grant No.2022YFA1402702)the National Science Foundation of China(Grant Nos.U2032213 and 12004243)+8 种基金the National Science Foundation of China(Grant No.12274412)the Interdisciplinary Program of Wuhan National High Magnetic Field Center(Grant No.WHMFC 202122)Huazhong University of Science and Technologythe support from the National Natural Science Foundation of China(Grant No.52101236)Guangdong Basic and Applied Basic Research Foundation(Grant No.2021B1515140014)the Guangdong Provincial Key Laboratory of Extreme Conditionsfinancial support from the National Key Research and Development Program of China(Grant Nos.2021YFA1600201 and 2023YFA1607402)the support of NSF-DMR-2003117supported by a beamtime allocation RB1910163 from the Science and Technology Facilities Council。
文摘Spinel compounds are of great interest in both fundamental and application-oriented perspectives due to the geometric magnetic frustration inherent to their lattice and the resulting complex magnetic states.Here,we applied x-ray diffraction,magnetization,heat capacity and powder inelastic neutron scattering measurements,along with theoretical calculations,to study the exotic properties of chromite-spinel oxides CoCr_(2)O_(4) and MnCr_(2)O_(4).The temperature dependence of the phonon spectra provides an insight into the correlation between oxygen motion and the magnetic order,as well as the magnetoelectric effect in the ground state of MnCr_(2)O_(4).Moreover,spin-wave excitations in CoCr_(2)O_(4) and MnCr_(2)O_(4) are compared with Heisenberg model calculations.This approach enables the precise determination of exchange energies and offers a comprehensive understanding of the spin dynamics and relevant exchange interactions in complicated spiral spin ordering.