The optical properties of copper and gold as a function of temperature

Abstract

The optical absorption spectra of copper and of gold have been measured polarimetrically as a function of temperature, while in ultra-high vacuum. The copper spectrum was obtained from 17-59 eV over the temperature range 77-920 °K and that of gold from 05-59 eV over the temperature range 295-770 °K. The main absorption peaks of both metals were found to vary with temperature and by comparison with calculations for the band structure of copper for various lattice parameters it was possible to identify peak positions with the following transitions: for copper, X₅ -> X₄prime at 397 eV, L₂prime -> L₁^u at 478 eV and L₁¹ -> E_F(L₂prime) at 532 eV, for gold L₂prime -> L₁^u at 408 eV and X₅ -> X₄prime at 455 eV.