Absence of ferromagnetic order in ultrathin Rh deposits grown under various conditions on gold

Abstract

Growth and magnetism of Rh films in the thickness range between 0 and 6 monolayers (ML) on Au(111) have been investigated over a wide range of coverages and deposition temperatures by means of variable temperature UHV-STM, Auger spectroscopy, and in situ Kerr effect measurements. Contrary to theoretical predictions, no ferromagnetism has been detected by the Kerr effect, irrespective of the film thickness and the growth conditions. This disagreement may be due to invalid theoretical predictions, however it is most probably due to the experimental impossibility to grow a perfectly uniform film: surface intermixing in the first stage of growth is observed. Even upon low temperature deposition (at 30 K and above), a Rh-Au surface alloy forms, followed by a Rh layer-by-layer growth.