Short wavelength, spin-polarized quantum-well states in high quality Cu films on FCC-Co(1 0 0)

The electronic structure of ultrathin Cu films deposited on top of an FCC-Co(1 0 0) film has been studied by angle- and spin-resolved photoemission. Deposition at liquid-nitrogen temperature allows the formation of sharp interfaces that produces well-defined quantum-well states in the Cu valence band. Furthermore, short-wavelength quantum-well states originating from the neck of the Cu Fermi surface are only visible after low-temperature deposition. Spin-resolved spectra show that these states, which are predicted to dominate oscillatory magnetic coupling in multilayers, exhibit minority spin character.