Surface magnons probed by spin-polarized electron energy loss spectroscopy

► Surface magnons can be investigated by spin-polarized electron spectroscopy. ► The effective exchange interaction in Fe films is sensitive to small changes in the structure. ► The surface magnons at Fe(1 1 0) are softer than the ones in bulk Fe. ► High wave vector magnons possess lifetimes as short as a few tens of femtoseconds.