University of Houston System

Yu-Yi Xue

Ching-Wu Chu

Ruling L Meng

Feng Chen

Stephen Tsui

Jason Shulman

Zhong L Du

A negative dielectric is induced by the application of a dc bias-electric field in aggregates of oxide nano-particles whose surfaces have been specially treated. The magnitude of the dielectric constant and the frequency where the negative dielectric constant occurs can be adjusted. Such material systems have profound implications in novel devices as well as in science development, e.g. unusual wave propagation, secured communication and ultra-high temperature superconductivity.

Generation and applications of negative dielectric constant materials

Highly oriented HgBa,Ca,Cu,O,on Ni-tapes with a buffer layer of Cr/Ag or Cr/(Ag&mdash;Pd) have been described with a high transition temperature are described along with, one and two step methods of manufacture.

High temperature superconducting tape and method of manufacture

A material having a superconducting transition temperature (T,) of 126 K under ambient pressure has been identified. The superconducting material belongs to a Ba&mdash;Ca&mdash;Cu&mdash;O compound family where the cation ratio of Ba:Ca:Cu is 2:2.5&plus;0.5:3.5&plusmn;0.5. The superconducting material is produced from precursor oxides having nominal formula Ba,Ca,Cu,O,wherein n&equals;3 or 4 and x is 0.4 to 1.0 and y is 0 to 0.8 using high-pressure synthesis. Final synthesis temperature was maintained at less than 950&deg; C. Formation of the superconducting material is sensitive to the state of the precursor oxides, the carbon content of the precursor, and the synthesis temperature, pressure and time.

Ba-Ca-Cu-O compositions superconducting at up to 126K and methods for making same

Highly oriented HgBa.sub.2 Ca.sub.2 Cu.sub.3 O.sub.8+.delta. on Ni-tapes with a buffer layer of Cr/Ag or Cr/(Ag--Pd) have been described with a high transition temperature are described along with, one and two step methods of manufacture.

Growing community of inventors

Houston, TX, United States of America

Yu-Yi Xue