Unveiling the complete dispersion of the giant Rashba split surface states of ferroelectric α − GeTe ( 111 ) by alkali doping

This paper shows how the detailed dispersion of the giant Rashba split surface states in the ferroelectric \ensuremath{\alpha}--GeTe(111) can be resolved by static ARPES and surface potassium doping. The authors further confirm the Rashba mechanism for these states by moving them into the occupied part of the band structure, in good agreement with state of the art DFT calculations.