Hope College Physics Department
Research Experiences for Undergraduates
Summer 2011
Project Summary


Project Title: Comparison of local nonlinearity in patterned superconducting chips composed of YBCO and TBCCO materials with vertical and slanted edge structures
Student Name: Sean Cratty
Student's Home Institution: Hope College
Research Advisor: Dr. Stephen Remillard
Source of Support:

This material is based upon work supported by the National Science Foundation under NSF-REU Grant No. PHY/DMR-1004811 as well as support from Mesaplexx Pty LTD.

Two of the most commonly used materials for high temperature superconducting devices are Tl2Ba2CaCu2O8 (TBCCO) and YBa2Cu3O7 (YBCO). Using a scanning electron microscope to look at manufactured superconducting chips composed of these materials, we are able to examine the edge structures of the patterned superconducting carriers and characterize them as either vertical walled (good manufacturing) or slanted walled (poor manufacturing). The superconducting materials exhibit nonlinear behavior at microwave frequencies as exhibited by second and third order intermodulation distortion (IMD). The IMD of YBCO and TBCCO samples with both slanted and bricked walls was compared along with the effects of hysteresis generated from an applied static magnetic field. At all temperatures the second order IMD in YBCO samples, in comparison to their TBCCO counterparts, display higher surface current densities at a constant drive current. The third order IMD of YBCO samples, on the other hand, are shown to be lower than those of TBCCO samples.
___________________________________________________________________________________________________________________________________________________________ Publications and Presentations:

S.K. Remillard, and S.R. Cratty; "Probing the Physical Origin of Locally Generated Nonlinearity in Microwave Superconducting Resonator Devices," Applied Superconductivity Conference, Portland, OR, October 8-12, 2012.

"Probing the Locally Generated Even and Odd Order Nonlinearity in Y-Ba-Cu-O and Tl-Ba-Ca-Cu-O (2212) Microwave Resonators around TC," Brooke M. Jeries*, Sean R. Cratty*, and S.K. Remillard, IEEE Trans. on Applied Superconductivity, Published on-line, Dec. 2012. Published in print, Vol. 23, no. 3, 9000105, (2013).