| Abstract: |
It is shown that recent measurements of field ion energy distributions from clean tungsten surfaces probe the density of metal states in the vicinity of the surface. We find j() = (2/kh)m| d3rm(r) z|2(-m), where j() is the ion current a , mand m are electronic metal eigenfunctions and eigenvalues in the presence of the external electric field used in field ionization and (z) is a function which is large near the noble gas atom. An explicit expression for (z) is given in the text. It is estimated that tungsten metal states with values of k|| at least as large as 0.5 {Aring}-1 make an appreciable contribution to j() where k|| is the electron momentum parallel to the surface. Return to Publications List |
