Electrically reconfigurable optical metamaterials based on orientationally ordered dispersions of metal nano-rods in dielectric fluids

Andrii B Golovin; Jie Xiang; Yuriy A Nastishin; Oleg D. Lavrentovich

doi:10.1117/12.858105

17 August 2010 Electrically reconfigurable optical metamaterials based on orientationally ordered dispersions of metal nano-rods in dielectric fluids

Andrii B Golovin, Jie Xiang, Yuriy A Nastishin, Oleg D. Lavrentovich

Author Affiliations +

Proceedings Volume 7775, Liquid Crystals XIV; 777502 (2010) https://doi.org/10.1117/12.858105
Event: SPIE Photonic Devices + Applications, 2010, San Diego, California, United States

Abstract

Optical metamaterials capture the imagination with potential applications such as sub-wave imaging, invisibility cloaking and solar energy collection. The challenge is to learn how to construct and reconfigure a metamaterial with a spatially varying refractive index. We describe an approach based on colloidal dispersion of metal nano-rods in a dielectric fluid placed in a non-uniform electric field. Because of the dielectrophoretic effect, the nano-rods accumulate in the regions with the maximum field and align along the field lines. High concentration of nano-rods lowers the effective local refractive index of the dispersion. The nano-rods are much smaller than the wavelength of light. We illustrate the approach with a dispersion of gold nanorods (length 40-70 nm, diameter 10-20 nm) in toluene, using flat and cylindrical cells. In the first case, the electric field is created by two mutually perpendicular electrodes, in the second case, it is created by two coaxial electrodes. When the field is applied, the initially isotropic dispersion of nanorods transforms into birefringent orientationally ordered structures with the director following the electric field lines. We describe how the optical properties of the field-induced structures are controlled by dichroism and birefringence of the dispersion and determine the spatial variation of the field-induced optical phase retardation. In cylindrical capillaries, the index gradient bends lights around the central electrode, thus reducing its visibility. Our approach can be used as a starting point for the development of self-assembled and reconfigurable optical metamaterials with optical properties controlled by the dielectrophoretic effect on submicron scales.

Citation Download Citation

Andrii B Golovin, Jie Xiang, Yuriy A Nastishin, and Oleg D. Lavrentovich "Electrically reconfigurable optical metamaterials based on orientationally ordered dispersions of metal nano-rods in dielectric fluids", Proc. SPIE 7775, Liquid Crystals XIV, 777502 (17 August 2010); https://doi.org/10.1117/12.858105

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available