Date of Award

Spring 2013

Document Type

Restricted Thesis

Terms of Use

© 2013 Atish Agarwala. All rights reserved. Access to this work is restricted to users within the Swarthmore College network and may only be used for non-commercial, educational, and research purposes. Sharing with users outside of the Swarthmore College network is expressly prohibited. For all other uses, including reproduction and distribution, please contact the copyright holder.

Degree Name

Bachelor of Arts


Physics & Astronomy Department

First Advisor

Keshav M. Dani

Second Advisor

Carl H. Grossman


We investigated the nonlinear response of an elliptical negative index metamaterial (eNIM) device using FTDT simulations. The device is a layered Ag-Si-Ag fishnet structure. Previous pump-probe experiments had shown that the device had the potential to serve as an all-optical picosecond switch. A visible pump pulse photoexcited silicon and quenched the transmission at around 1.6 μm. We used simulation to explore geometric optimizations to the switching ratio. We simulated the effects of reducing the anisotropy of the holes and found that improving the sidewall angle to 4° improved the switching ratio by 2 dB. Adding extra layers to the device did not appreciably change the switching ratio. Adding a second weakly coupled device increased the switching ratio by about 1 dB. We also investigated the effects of manufacturing improvements in the silver layer. Improving the scattering frequency γs of the Ag layer leads to a 2 dB improvement in switching ratio. If all of these manufacturing improvements can be realized, the device can provide picosecond switching of 3.3 dB for approximately 25 W of power.