A new class of artificially structured materials called metamaterials makes it possible to achieve electromagnetic properties that do not exist in nature. In this article, we review the recent progress made in the area of optical metamaterials, specifically artificial magnetism and negative-index metamaterials. It was predicted that nanostructured metamaterials could provide magnetic responses and negative refractive indexes at optical frequencies. To date, optical metamagnetics have been fabricated to demonstrate magnetic responses in the infrared range and across the entire visible spectrum. Metamaterials showing negative refractive indexes, also called negative-index materials (NIMs), have also been demonstrated in the infrared range and at the border with the visible spectral range. Additionally, we report the results of a sample that displays NIM behavior for red light at a wavelength of 710 nm and another sample that displays double-negative NIM behavior at 725 nm. Both observations represent the shortest wavelengths so far at which NIM behavior has been observed for light. We also discuss the fabrication challenges and the impact of fabrication limitations, specifically the effect of surface roughness of the fabricated structures, on the optical properties of the metamaterials.
Uday K. Chettiar can be reached at Birck Nanotechnology Center, 1205 W. State St, West Lafayette, IN 47907, USA; tel. 765-496-3317, and e-mail firstname.lastname@example.org.
Chettiar is a PhD degree candidate in professor Vladimir Shlaev's Photonics and Spectroscopy Laboratory at Purdue University. He received a bachelor's degree in electrical engineering from the Indian Institute of Technology, Mumbai, India, in 2003. His current research interests include design and analysis of optical metamaterials. Chettiar is member of the Optical Society of America, has published more than 13 papers in peer-reviewed journals, and has given several talks at international scientific conferences, including two invited talks. In addition, he was a gold medalist in the Indian National Physics Olympiad and is a recipient of Benjamin Franklin-Meissner fellowship at Purdue.
Shumin Xiao can be reached at the Birck Nanotechnology Center, 1205 W. State St., West Lafayette, IN 47907, USA; tel. 765-496-3308, and email email@example.com.
Xiao is working toward her PhD degree in the Nanophotonics and Plasmonics Laboratory at Purdue University. She received her BS degree from the Department of Physics, Sun Yat-Sen University, Guangzhou, China, in 2003, and her MS degree from the Department of Optical Science and Engineering, Fudan University, Shanghai, China. Xiao's research areas focus on metamaterials.
Alexander V. Kildishev can be reached at Birck Nanotechnology Center, 1205 W. State St., West Lafayette, IN 47907, USA; tel. 765-496-3196, and e-mail firstname.lastname@example.org.
Kildishev is a senior member of IEEE, and is a member of the Applied Computational Electromagnetics Society and ICS. He also is currently a principal research scientist at the Photonics and Spectroscopy Laboratory in the Birk Nano technology Center, where he has been a member of the School of Electrical and Computer Engi neering at Purdue University since 1998. Kildishev received his MS and PhD degrees in electrical engineering from the Kharkov State Polytechnical University in the Ukraine. He has worked as a senior scientist at the Institute of Electrodynamics, Academy of Sciences, Ukraine. His primary research interest is the development of advanced computational methods for spatial harmonic/modal analysis in general radiation and scattering problems in applied electromagnetics and optics, including optimization of plasmonic metamaterials. Kildishev's publications include four book chapters, four patents, and more than 70 articles in peer reviewed journals, with more than 450 citations.
Wenshan Cai can be reached at Geballe Laboratory for Advanced Materials, Stanford University, 476 Lomita Mall, Stanford, CA 94305, USA; tel. 650-498-6256, and e-mail email@example.com.
Cai is a postdoctoral researcher at Stanford University. He received his BS and MS degrees from the Department of Electronics Engineering at Tsinghua University, Beijing, China, in 1999 and 2002, respectively. From 2002 to 2008, Cai worked for his PhD degree in electrical and computer engineering at Purdue University. His research areas of interest include optical metamaterials, plasmonics optics, optoelectronics, and nanoscale photonic materials and devices. Cai has authored or co-authored more than 30 journal articles and conference papers. He also is the recipient of several prestigious awards, including the Chinese Government Award for Outstanding Students Abroad and the Optical Society of America New Focus/Bookham Student Award.
Hsiao-Kuan Yuan can be reached at 805 NE 62nd Ave., Apt. #P, Hillsboro, OR 97124, USA; tel. 765-490-5250, and e-mail firstname.lastname@example.org.
Yuan is pursuing a career with Intel Corporation, beginning in September 2008. He received his BS degree from the Department of Chemical Engineering and a MS degree from the Department of Materials Science and Engineering, both at National Taiwan University (NTU). After graduation from NTU, Yuan was a process engineer at the Taiwan Semiconductor Manufacturing Company for two years. Afterward, Yuan was admitted to Purdue University and earned his PhD degree in electrical and computer engineering there.
Vladimir P. Drachev can be reached at the Birck Nanotechnology Center, 1205 W. State St., West Lafayette, IN 47907, USA; tel. 765-496-3539, and e-mail email@example.com.
Drachev is a senior research scientist in the Birck Nanotechnology Center and School of Electrical and Computer Engineering at Purdue University. He received his MS degree from Novosibirsk State University, Russia, in 1980, and his PhD degree from the Institute of Automation and Electrometry, Russian Academy of Sciences in 1995. From 1999 to 2001, Drachev worked at New Mexico State University. He joined Purdue in 2002. Drachev's research interests include plas-monics, metamaterials, and surface-enhanced Raman spectroscopy.
Vladimir M. Shalaev can be reached at Birck Nanotechnology Center, 1205 W. State St., West Lafayette, IN 47907; tel. 765-494-9855, and e-mail firstname.lastname@example.org.
Shalaev is the Robert and Anne Burnett Professor of Electrical and Computer Engineering and a professor of biomedical engineering at Purdue University. He specializes in nanophotonics, plasmonics, and optical metamaterials. Shalaev made pioneering contributions to the optics of fractal and percolation composites, and their applications for surfaceenhanced Raman spectroscopy, and to the field of optical metamaterials, including the first experimental observation (collectively with his research team at Purdue University) of negative refractive index in the optical range and magnetism across the entire visible range. Shalaev received several awards for his research in the field of nanophotonics and metamaterials. He has authored or co-authored two books, 20 invited book chapters, and about 300 research publications. In addition, Shalaev is a co-editor for several books in the area of nanoscale optics and an editorial board member for a number of research journals. He is a Fellow of the American Physical Society, the International Society for Optical Engineering, and the Optical Society of America.