SIZE-DEPENDENT DIELECTRIC RESPONSE OF SMALL METAL PARTICLES

The complex dielectric function of small metal particles is size dependent at microwave and radio frequencies. This was measured for particle diameters between 10 nm and 10-mu-m. In contrast to bulk electromagnetic response, the real part of the dielectric function in the small particles is positive and goes through a maximum. In addition, the temperature dependence of the loss index was found to change from positive to negative behavior near 1-mu-m.