Structural, magnetic and magnetoelectric properties in spin-frustrated α-Cu5O2(SeO3)2Cl2

kakarla D Chandrasekhar^1*

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, email:chandu@g-mail.nsysu.edu.tw

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