Giant Drop of Magnetic Hysteresis with Decreasing Thickness of Cr-Buffer Layer of CoFe/Cu Superlattices

The effect of Cr-buffer-layer thickness on the structure, giant magnetoresistance, and coercivity of DC sputtered Cr(tCr)/[Co90Fe10(15A)/Cu(23A)]8/Cr(10A) superlattices has been investigated. A drastic change of hysteresis in a short interval of the buffer layer thickness (15 ÷ 20 A) has been revealed. It has been shown that in superlattices with low coercivity the (111) texture is present, whereas superlattices without texture demonstrate a large coercivity and high GMR ratio.