Research on Millimeter Wave Dielectric Materials.
Abstract
Much of the early effort in this program was devoted to single crystal strontium barium niobate (SBN), a tungsten bronze with an unusually large room-temperature dielectric response. More recently, other tungsten bronzes such as potassium lithium niobate (KLN) and barium strontium potassium sodium niobate (BSKNN) have been prepared and studied to elucidate the role of unfilled crystallographic sites in influencing dielectric loss. Currently, we are developing preparation techniques for morphotropic phase boundary (MPB) bronzes, such as lead barium niobate (PBN), which should exhibit exceptionally large nonlinear electrical and optical response for a Pb:Ba ratio of 60:40, where it undergoes a transition from tetragonal to orthorhombic form. Large, high quality BSKNN single crystals have now been developed for free-space millimeter wave measurements. Measurements on BSKNN and SBN at room and cryogenic temperatures are reported, and a theoretical model has been successfully formulated for the dielectric response. Low frequency data are also presented for a new orthorhombic bronze, SCNN, which shows high suitability for millimeter wave development.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1986
- Accession Number
- ADA173017
Entities
People
- J. R. Oliver
- R. R. Neurgaonkar