Structural, magnetic and magnetoelectric properties in spin-frustrated α-Cu5O2(SeO3)2Cl2
kakarla D Chandrasekhar1*
1Department of Physics, National Sun Yat-sen University, KAOHSIUNG, Taiwan
2Center of Crystal Research, National Sun Yat-sen University, KAOHSIUNG, Taiwan
3Department of Physics, National Central University, Chung-Li, Taiwan
4Institute of Physics, National Chiao Tung University, Hsinchu, Taiwan
5National Synchrotron Radiation Research Center, National Synchrotron Radiation Research Center, Hsinchu, Taiwan
6Department of Materials and Optoelectronic Science, National Sun Yat-sen University, KAOHSIUNG, Taiwan
* Presenter:kakarla D Chandrasekhar,
Single crystals of α-Cu5O2(SeO3)2Cl2 are successfully prepared by the chemical vapor transport method and their structural, magnetic, thermal, and dielectric properties as a function of temperature and magnetic field are investigated. Magnetization and specific heat measurements indicate a long-range antiferromagnetic transition at TN = 32 K. The spin ordering with propagation vector of q = (½00) below TN is determined from the neutron diffraction patterns. Dielectric data reveal an anomaly (TE) near TN, indicating spin-induced electric polarization. Magnetic field-dependent dielectric measurements below TN = 32 K suggest a notable magnetodielectric effect with the scaling of magnetodielectric  M2, indicating spin-lattice coupling. In addition, weak pyrocurrent and polarization are detected below TN, suggesting spin-induced multiferroic behavior. These studies provide evidence that the honeycomb-lattice α-Cu5O2(SeO3)2Cl2 is a new multiferroic material.

Keywords: Multiferroics, Antiferromagnetic order, Magnetoelectric effect, Spin-frustrated system