en مگنتو اپتیک Magneto-Optics پژوهشي Research <span style="font-size:11pt"><span new="" roman="" style="font-family:" times=""><span style="font-weight:bold">In this study, copper cobalt ferrite nanoparticles were synthesized by chemical formula Co_1-xCu_xFe₂O₄ and (x=0, 0.2, 0.4, 0.6, 0.8, 1) by co-precipitation method. The X-ray diffraction pattern of the samples confirmed the single-phase spinel structure of the fabricated nanoparticles and the average size of the crystals was calculated from the entire width of the diffraction peak with the highest intensity and Scherrer relationship. Using transmission electron microscope images, the nanoparticle size was about 10 nm. The magnetic properties of copper cobalt ferrite nanoparticles were measured by AGFM and it was seen that with increasing substitution of copper Cations instead of cobalt Cations in the samples, the amount of induction decreased and the saturation magnetization first increased and then decreased. In order to investigate the Faraday effect on copper cobalt ferrite nanoparticles, the transmittance values were measured using a laboratory experiment and their graphs were plotted in terms of the applied magnetic field, all of which were in agreement with the theory. In addition, transmittance was investigated for two angular positions of the analyzer at -45˚ and +45˚ in different fields.</span></span></span> Magnetic nanoparticles, Ferrite, Co-precipitation, Faraday rotation 221 228 http://ijop.ir/browse.php?a_code=A-10-970-1&slc_lang=en&sid=1 Mohammad Moradi Moradi@sku.ac.ir 10031947532846005148 10031947532846005148 No Department of Physics, University of Shahrekord, Shahrekord, Iran Forouzan Habibi Forouzan.Habibi1990@gmail.com 10031947532846005149 10031947532846005149 Yes Department of Physics, University of Shahrekord, Shahrekord, Iran Asieh Rafiee momo_1344@yahoo.com 10031947532846005150 10031947532846005150 No Department of Physics, University of Shahrekord, Shahrekord, Iran