Dr. Paul E. Crittenden Profile

Dr. Paul E. Crittenden

Assistant Professor at Jacksonville Univ

SPIE Involvement:

Author

Publications (3)

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 | 4 March 2004 Paper

Near-field and far-field characterization of stratified chiral structures

Ezekiel Bahar, Paul Crittenden

Proceedings Volume 5270, (2004) https://doi.org/10.1117/12.516790

KEYWORDS: Interfaces, Electromagnetism, Magnetism, Scattering, Transform theory, Near field, Polarization, Agriculture, Fourier transforms, Maxwell's equations

Read Abstract +

Full wave expression for the electromagnetic fields scattered by a rough interface between two chiral materials with laterally varying electromagnetic properties are obtained from generalized telegraphists equation for irregular media. The telegraphists equation are a set of coupled differential equations for the forward and backward wave amplitudes of the transverse components of the magnetic field and the electric field. They can be used to determine the electromagnetic near and far fields scattered above and below the interface. This has direct applications to the detection of chiral materials, the discrimination between different chiral media and the optimization of desired electromagnetic characteristics of artificial chiral materials. To derive the generalized telegraphists equations, no simplfying assumptions are made about the characteristics of the rough interface, the frequency of the source, or the locations of the source and observation points. Therefore, they provide advantageous starting points for deriving solutions to a broad variety of physical problems. In electrical engineering possible applications include integrated optic devices, polarization transformers, modulators and directional couplers. In all these applications, sub-wavelength fluctuations at the interfaces between the media can significantly affect the physical characteristics of the chiral structure. The analysis can be used in the detection, characterization and design of chiral structures consisting of complex media with engineering, biomedical, agricultural and biosecurity applications.

Proceedings Article | 9 July 2003 Paper

Electromagnetic characterization of stratified chiral structures in nanotechnology

Paul Crittenden, Ezekiel Bahar

Proceedings Volume 5218, (2003) https://doi.org/10.1117/12.503744

KEYWORDS: Interfaces, Transform theory, Magnetism, Electromagnetism, Wave propagation, Scattering, Fourier transforms, Nanotechnology, Electromagnetic radiation, Reflection

Read Abstract +

The circularly polarized wave decomposition of Maxwell's equations for electromagnetic wave propagation in chiral materials is the starting point for this analysis. The Fourier transforms of the Green's functions for the electromagnetic waves on both sides of a flat interface between two semi-infinite chiral materials are derived. These harmonic solutions are expressed in terms of the characteristic right and left circularly polarized waves. Through a path deformation in the complex plane, the Green's functions are converted into alternate, modal, representations that are suitable for the complete expansion of the electromagnetic fields above and below a rough interface between two chiral materials with laterally varying material properties. From these representations, generalized Fourier teransform pairs are derived. The generalized Fourier transforms can be used to obtain two sets of coupled ordinary differential equations for the field transforms in terms of the forward and backward wave amplitudes of the transverse fields. Iterative solutions of these generalized telegraphists equations are found. From these solutions the fields can be found under appropriate assumptions. Since no a priori assumptions are made about the surface height, the frequency of the source, or the material parameter this work could be applied to nanotechnology involving stratified chiral structures.

Proceedings Article | 25 October 1999 Paper

One- and two-dimensionally rough-surface radar backscatter cross section based on a stationary two-scale full-wave approach

Ezekiel Bahar, Paul Crittenden

Proceedings Volume 3784, (1999) https://doi.org/10.1117/12.366701

KEYWORDS: Radar, Backscatter, Scattering, Numerical analysis, Composites, Chemical elements, Modulation, Electro optics, Polarization, Silicon

Read Abstract +

The full wave approach is applied to one and two dimensionally rough surfaces that are characterized by Gaussian surface height probability density functions. The full wave solutions are compared with published analytical and numerical solutions for one dimensional rough surfaces. The decomposition of the rough surface into smaller and larger rough scale surfaces is not restricted by the small perturbation limitations when the two-scale full wave approach is used. Thus the mean square height of the smaller scale surface is not restricted to small values. In the small slope limit, the total rough surface is regarded as a small scale surface and the corresponding solution is given by the single scatter original full wave solution. In the high frequency limit, the total rough surface is regarded as a large scale surface and the full wave solution reduces to the physical optics solution. For the intermediate two-scale case, the radar cross sections are obtained by regarding the rough surface as an ensemble of arbitrarily oriented patches of small scale surfaces that ride upon the large scale surface. The rough surface radar cross sections are expressed as weighted sums of two cross sections. It is shown that the full wave solutions are stationary over a wide range of patch sizes.

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