Systematic study of the focal shift effect in planar plasmonic slit lenses.
نویسندگان
چکیده
In this paper, we systematically studied the focal shift effect in planar plasmonic slit lenses. Through theoretical derivations and numerical simulations, we found that there is a focal length shift between the traditional design model and the finite-difference time-domain simulations. The shift is not only dependent on the Fresnel number (FN) of the lens, like traditional dielectric lenses, determined by the lens width and the designed focal length, but also on the surface plasmon polariton (SPPs) interaction on the lens surfaces, dependent on the slit numbers. We also found that the FN-induced focal shift is predominant when FN < 1. However, the SPP interaction-induced focal shift plays a major role when FN > 1. An approximated theoretical model is presented to estimate the focal shift of plasmonic slit lens with FN < 1.
منابع مشابه
A spiral plasmonic lens with directional excitation of surface plasmons
Conventional plasmonic lenses are composed of curved slits carved through metallic films. Here, we propose a new plasmonic lens based on a metallic slit with an auxiliary groove. When the lens is illumined normally, only inward surface plasmon polaritons (SPPs) can be generated and then focused into a hot spot at the center of the lens. The focusing effect is theoretically investigated by varyi...
متن کاملImaging slit-coupled surface plasmon polaritons using conventional optical microscopy.
We develop a technique that now enables surface plasmon polaritons (SPPs) coupled by nano-patterned slits in a metal film to be detected using conventional optical microscopy with standard objective lenses. The crux of this method is an ultra-thin polymer layer on the metal surface, whose thickness can be varied over a nanoscale range to enable controllable tuning of the SPP momentum. At an opt...
متن کاملMelatonin Reduces Cataract Formation and Aldose Reductase Activity in Lenses of Streptozotocin-induced Diabetic Rat
Background: The relationship between the high activity of aldose reductase (AR) and diabetic cataract formation has been previously investigated. The purpose of the present study was to determine the preventing effect of melatonin on streptozotocin (STZ)-induced diabetic cataract in rats.Methods: 34 adult healthy male Sprague-Dawely rats were divided into four groups. Diabetic control and diabe...
متن کاملAdjustable Plasmonic Bandgap in One-Dimensional Nanograting Based on Localized and Propagating Surface Plasmons
Compared to the long history of plasmonic gratings, there are only a few studies regarding the bandgap in the propagation of plasmonic surface waves. Considering the previous studies on interpretation of plasmonic bandgap formation, we discuss this phenomenon using the effect of both surface plasmon polariton (SPP) and localized surface plasmon (LSP) for our fabricated one-dimensional metallic-...
متن کاملControl the dispersive properties of compound plasmonic lenses
We propose novel compound plasmonic lenses, which consist of metal–insulator–metal waveguides (MIMWGs) and phase zone plates (PZPs), with controllable dispersive properties. Numerical simulation results show that this new type of compound plasmonic lens is capable of not only minimizing the chromatic aberration but also rearranging the order of focal positions for incident light at visible freq...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Nanotechnology
دوره 23 44 شماره
صفحات -
تاریخ انتشار 2012