Measurements of complex refractive indices of metals at several wavelengths by frustrated total internal reflection due to surface plasmon resonance

By employing a modified Otto's configuration for measuring surface plasmon resonance that has been proposed by Bliokh and his coworkers [Appl. Phys. Lett. 89, 021908 (2006)] we have obtained complex refractive indices of metals at several wavelengths. We demonstrate that the configuration has high potential for obtaining dispersion relations of metal conductors in bulk samples as well as in thin films from the visible to the near-infrared wavelength region. Furthermore, we show that the configuration enables us to obtain the complex refractive indices of metals or a thickness or refractive index of a dielectric layer on the metal at different points simultaneously. We have constructed a measurement system and carried out basic experiments. The experimental results agreed well with numerically simulated values or published ones. (C) 2008 Optical Society of America.