Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 3 of 3
Full-Text Articles in Entire DC Network
Scaling Of Losses With Size And Wavelength In Nanoplasmonics And Metamaterials, Jacob B. Khurgin, Greg Sun
Scaling Of Losses With Size And Wavelength In Nanoplasmonics And Metamaterials, Jacob B. Khurgin, Greg Sun
Physics Faculty Publications
We show that, for the resonant metal-dielectric structures with sub-wavelength confinement of light in all three dimensions, the loss cannot be reduced considerably below the loss of the metal itself unless one operates in the far IR and THz regions of the spectrum or below. Such high losses cannot be compensated by introducing gain due to Purcell-induced shortening of recombination times. The only way low loss optical meta-materials can be engineered is with, as yet unknown, low loss materials with negative permittivity.
In Search Of The Elusive Lossless Metal, Jacob B. Khurgin, Greg Sun
In Search Of The Elusive Lossless Metal, Jacob B. Khurgin, Greg Sun
Physics Faculty Publications
We show that when one looks beyond the Drude model of metal conductivity, the metals that may be extremely lossy for low frequency electromagnetic waves can become perfectly lossless in the mid-IR region or higher, while retaining the essential metallic characteristic of negative permittivity even at those frequencies. We identify that the transition to the lossless regime occurs when the interatomic distances in the lattice exceed certain values, typically a factor of two larger than those occurring in nature. We believe that advances in nanoassembly may render lossless metals feasible with revolutionary implications for the fields of plasmonics and metamaterials.
Aberration-Free Negative-Refractive-Index Lens, Jiajun Chen, Cosmin Radu, Ashok Puri
Aberration-Free Negative-Refractive-Index Lens, Jiajun Chen, Cosmin Radu, Ashok Puri
Physics Faculty Publications
The aberrations of a spherical lens composed of left-handed materials are studied in this letter. Five Seidel aberrations (spherical, coma, astigmatism, field curvature, and distortion) as a function of the refractive index n and shape factor q of the lens are considered. Our numerical calculations show that the negative refractive index gives much larger windows of small values of aberrations than the positive index, which will significantly enhance the flexibility for the design of an optical lens. Two possible regions with optimized aberrations are proposed: n = −1, q = −2.2 and n = −0.81 and q = 0.83