Ultrathin vanadium films on Cu(001): structure and magnetism

Abstract

X-ray photoelectron diffraction (XPD), low energy electron diffraction (LEED), and magnetic linear dichroism in angular distributions of photoelectrons (MLDAD) have been used to study the structural and magnetic properties of V thin films on Cu(001). For room-temperature growth, XPD and LEED data indicate that below 1 monolayer (ML), equivalent V films exhibit a (2×1) structure that evolves to four domains of bcc (110) at coverages above 1 ML. This multi-domain structure produces a LEED pattern often referred to as ‘(3×1)’. This structure persists to V coverages as high as 100 ML, and the LEED and XPD angular scans indicate that V in these films retains the bulk V lattice constant. MLDAD results for 1–5 ML V films at room temperature and at 150 K provide no evidence for in-plane magnetic ordering. Annealing to 450° C results in V clustering at low coverages accompanied by Cu diffusion. For thick V films, the primary affect of annealing is interdiffusion of Cu and V.