1. School of Electrical Engineering; Korea University; Anam-dong 5-ga Seongbuk-gu Seoul 136-701 Korea
2. Materals & Components Lab.; LG Advanced Research Institute; LG Electronics, Baumoe-ro 38 Seocho-gu Seoul 137-724 Republic of Korea
3. Department of Electrical; Computer, and Systems Engineering; Rensselaer Polytechnic Institute; Troy NY 12180 USA