Mr. Sushanth Reddy Amanaganti Profile

Sushanth Reddy Amanaganti

at Mahindra École Centrale

SPIE Involvement:

Author

Publications (2)

This will count as one of your downloads.

You will have access to both the presentation and article (if available).

DOWNLOAD NOW

This content is available for download via your institution's subscription. To access this item, please sign in to your personal account.

Email or Username Forgot your username?

Password Forgot your password?

Show

Keep me signed in

No SPIE account? Create an account

Proceedings Article | 30 April 2019 Presentation + Paper

High refractive index dielectric rings in liquid crystals as tunable metasurfaces

Sushanth Reddy Amanaganti, Jayasri Dontabhaktuni

Proceedings Volume 11025, 110250J (2019) https://doi.org/10.1117/12.2520768

KEYWORDS: Magnetism, Dielectrics, Liquid crystals, Refractive index, Tellurium, Terahertz radiation, Electromagnetism, Gallium arsenide, Molecules, Finite-difference time-domain method

Read Abstract +

Dielectric structures with high refractive indices give rise to Mie-type resonances with a remarkably high localization of electric and magnetic fields inside the dielectric structures due to excitation of selective multipolar modes. It is known that the specific geometries like rings give rise to magnetic responses comparable to the electric modes in metallic structures. In the present work, we study the resonant characteristics of high refractive index circular and square dielectric rings using full-wave electromagnetic simulations. Effect of geometry, thickness of the structures and refractive index on the electromagnetic response is studied in the sub-wavelength regime. Square rings are observed to exhibit sharper resonances at lower frequencies compared to the circular rings as a consequence of enhanced field localization within the dielectric structures. It is observed that the thickness plays a major role in the excitation of various resonant modes. Electric modes are predominantly sustained in the thinner rings (thickness lesser compared to the lattice constant) while thicker rings support magnetic modes predominantly. When such rings are placed in birefringent liquid crystal medium orientation of the liquid crystal molecules are observed to enhance certain modes over the other giving rise to tunable metasurfaces. Further, novel modes such as electric dipole+electric quadrupole and toroidal modes are observed, hitherto not observed in air.

Proceedings Article | 8 February 2018 Paper

Electromagnetic response of dielectric nanostructures in liquid crystals

S. Amanaganti, D. R. Chowdhury, M. Ravnik, J. Dontabhaktuni

Proceedings Volume 10555, 105551F (2018) https://doi.org/10.1117/12.2289415

KEYWORDS: Dielectrics, Liquid crystals, Nanostructures, Resonators, Tellurium, Nanoparticles

Read Abstract +

Sub-wavelength periodic metallic nanostructures give rise to very interesting optical phenomena like effective refractive index, perfect absorption, cloaking, etc. However, such metallic structures result in high dissipative losses and hence dielectric nanostructures are being considered increasingly to be an efficient alternative to plasmonic materials. High refractive index (RI) dielectric nanostructures exhibit magnetic and electric resonances simultaneously giving rise to interesting properties like perfect magnetic mirrors, etc. In the present work, we study light-matter interaction of cubic dielectric structures made of very high refractive index material Te in air. We observe a distinct band-like structure in both transmission and reflection spectra resulting from the interaction between magnetic and electric dipolar modes. FDTD simulations using CST software are performed to analyse the different modes excited at the band frequencies. The medium when replaced with liquid crystal gives rise to asymmetry in the band structure emphasizing one of the dominant magnetic modes at resonance frequencies. This will help in achieving a greater control on the excitation of the predominant magnetic dipolar modes at resonance frequencies with applications as perfect magnetic mirrors.

My Library

You currently do not have any folders to save your paper to! Create a new folder below.

Folder Name

Folder Description

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks. You are receiving this notice because your organization may not have SPIE eBooks access.*

*Shibboleth/Open Athens users─please sign in to access your institution's subscriptions.

To obtain this item, you may purchase the complete book in print or electronic format on SPIE.org.

ORGANIZATIONAL
Sign in with credentials provided by your organization.

Organizational Username

Organizational Password

Show/Hide Password

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

Members:

Non-members: ADD TO CART

Keywords/Phrases

Search In:

Publication Years