The optical constants (n, k) of single crystalline InBi have been determined using a two-angle method applying Fresnel’s equations. The complex dielectric constant was then calculated using the relation ε* = ε1 − iε2, where ε1 = n2 − k2 and ε2 = 2nk. Assuming a free-electron model, the volume plasma resonance energy was found from the crossover position of the n and k curves to be 10.3 eV. The energy loss functions − Im[1/ε] and − Im[l/(ε + 1)], which have been interpreted as having maxima at the volume and surface plasma frequencies, respectively, when interband transitions are not significant, were plotted using the n and k data. These values were in general agreement with those obtained from the crossover point on the n and k curves and from the Ritchie relation Es = Ev/√2.
© 1976 Optical Society of America 999
Roger L. Kroes, Roger C. Linton, and Frank E. Martin, "Vacuum-ultraviolet optical properties of single-crystal InBi," J. Opt. Soc. Am. 66, 999-1003 (1976)