en عمومى General پژوهشي Research In this paper, the magnetic properties of carbon based material, graphene is studied, which is generated by laser ablation in cryogenic media. Transmission electron microscopy (TEM) and alternating gradient force magnetometer (AGFM) are applied to investigate the graphene morphology and magnetic properties, respectively. The graphene synthesized by the laser ablation method exhibits diamagnetic behavior. However the magnetic transition from diamagnetic to paramagnetic effect is lucidly observed by functionalizing the graphene sample with silver atoms. Alternating gradient force magnetometer (AGFM), Diamagnetic, Ferromagnetic, Graphene, Paramagnetic, Transmission electron microscopy (TEM). 35 42 http://ijop.ir/browse.php?a_code=A-10-424-1&slc_lang=en&sid=1 Parviz Parvin parvin@aut.ac.ir 10031947532846001248 10031947532846001248 Yes Department of Energy Engineering and Physics, Amirkabir University of Technology, Tehran, Iran Zohreh Ghorannevis ghoranneviszohreh@gmail.com 10031947532846001249 10031947532846001249 No Department of Physics, Karaj Branch, Islamic Azad University, Karaj, Iran Mohsen Mehrabi m.mehrabi@kashanu.ac.ir 10031947532846001250 10031947532846001250 No Department of Energy Engineering and Physics, Amirkabir University of Technology, Tehran, Iran Pooria Taghdiri pooria_taghdiri@aut.ac.ir 10031947532846001251 10031947532846001251 No Department of Energy Engineering and Physics, Amirkabir University of Technology, Tehran, Iran Zahra Mortazavi z.mortazavi@yahoo.com 10031947532846001252 10031947532846001252 No Department of Energy Engineering and Physics, Amirkabir University of Technology, Tehran, Iran Ali Reyhani a.reyhani@yahoo.com 10031947532846001253 10031947532846001253 No Department of Energy Engineering and Physics, Amirkabir University of Technology, Tehran, Iran