English

Physical properties in nano-crystalline Ho$_2$CoMnO$_6$

Strongly Correlated Electrons 2019-09-25 v1

Abstract

3dd based double perovskite materials have received much attention in recent years due to their exotic magnetic structure and magneto-electric coupling. In this work we have prepared and studied the nano-crystalline sample of Ho2_2CoMnO6_6. Structural, magnetic, Raman and dielectric properties have been studied in detail. The structural analysis shows that the sample crystallize in monoclanic crystal structure with \textit{P2_1/n} phase group. The X-ray photoelectron spectroscopy have been employed to confirms the charge state of cations presents in the material. Magnetic study shows that the sample undergoes a paramagnetic to ferromagnetic phase transition around TcT_c \sim85 K. The isothermal magnetization measurements shows hysteresis curve hence confirm ferromagnetic behavior at low temperature. Temperature dependent Raman study reveals that there is spin phonon coupling in the sample marked by deviation in phonon mode from anharmonic behavior. Dielectric response of Ho2_2CoMnO6_6 shows the large dispersion and large dielectric constant. Impedance spectroscopy and electrical modulus study reveal that system shows deviation from ideal Debye model. AC conductivity have been studied as a function of both temperature and frequency. We found that the conduction mechanism is obeyed by Jonscher's model. The exponent factor nn is suggest that the material deviates from ideal Debye model.

Keywords

Cite

@article{arxiv.1909.10590,
  title  = {Physical properties in nano-crystalline Ho$_2$CoMnO$_6$},
  author = {Ilyas Noor Bhatti and Imtiaz Noor Bhatti and Rabindra Nath Mahato and M. A. H. Ahsan},
  journal= {arXiv preprint arXiv:1909.10590},
  year   = {2019}
}

Comments

13 pages, 17 figures