Exchange coupling between Cr and ferromagnetic thin films

Abstract

Exchange bias has been observed in Ni81Fe19/Cr bilayers. The exchange bias field for Cr thickness tCr larger than 62 Å increases with tCr and levels off at tCr=150 Å, whereas coercivity increases without saturation. The blocking temperature increases with the Cr thickness. Due to the presence of commensurate spin density waves in the thicker but strained Cr layers, blocking temperature as much as 425 K has been observed. Exchange bias has also been observed in Co/Cr bilayers.