Nanodielectrics with Nonlinear Response for High Power Microwave Generation

This proposal addresses the development of nanostructured dielectric materials with a nonlinear parametric response, designed to be integrated into a high power capacitor system. Recent developments in nanodielectrics utilizing metal-insulator transition and plasmon based phenomena have resulted in non linear capacitor dielectrics with ultra high dielectric constants but relatively low breakdown voltage and energy densities. The proposed nanostructured capacitor dielectric is composed of metal nanoparticles arranged with a high level of orientation in a polymer matrix. The nanoparticles are arranged in close proximity to each other in a two dimensional matrix to take advantage of charge coupling that results from Plasmon interactions. Furthermore, several 2D nanoparticle matrices are arranged in a 3D matrix in a precise manner to elevate the breakdown strength of the composite dielectric. The nanoparticles can have different size and density and their major role is to increase the dielectric constant and enhance the non linear behavior of the dielectric. A vector network analyzer will be used to measure the complex dielectric permittivity and permeability in microwave frequencies from 50MHz to 67GHz and Terahertz time domain spectroscopy in both transmission, and reflection modes, will be used to measure both the complex refractive index and the wave impedance. This will allow extraction of the permittivity and permeability values in the terahertz frequency range. The Phase I program will focus in the design, fabrication and parametric evaluation of composite dielectrics comprising of 2D nanoparticle arrays in a 3D matrix, where the number of arrays will be varied along with nanoparticle size and density. Basic capacitor properties such as DC and AC breakdown strength, dissipation factor, and capacitance will be measured at select frequencies and temperatures