We present angle-resolved photoemission data from Cu(111). Using a focused 6 eV continuous wave laser for photo-excitation, we achieve a high effective momentum resolution enabling the first detection of the Rashba spin splitting in the Shockley surface state on Cu(111). The magnitude of the spin-splitting of Delta k ~ 0.006 A^-1 is surprisingly large and exceeds values predicted for the analogous surface state on Ag(111) but is reproduced by first principles calculations. We further resolve a kink in the dispersion which we attribute to electron-phonon coupling.
@article{arxiv.1301.5991,
title = {Spin-orbit splitting of the Shockley surface state on Cu(111)},
author = {A. Tamai and W. Meevasana and P. D. C. King and C. Nicholson and A. de la Torre and E. Rozbicki and F. Baumberger},
journal= {arXiv preprint arXiv:1301.5991},
year = {2015}
}