Đang chuẩn bị liên kết để tải về tài liệu:
Handbook of High Temperature Superconductor Electronics Part 3

Không đóng trình duyệt đến khi xuất hiện nút TẢI XUỐNG Tải xuống

Tham khảo tài liệu 'handbook of high temperature superconductor electronics part 3', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 2 Epitaxial Growth of Superconducting Cuprate Thin Films David P. Norton University of Florida Gainesville Florida U.S.A. 2.1 INTRODUCTION In 1986 Bednorz and Muller reported a superconducting transition temperature greater than 30 K in a multicomponent oxide compound namely LiOjBa. .-CuO4-s 1 . The discovery of other layered copper oxide materials with superconducting transition temperatures Tc exceeding the boiling point of liquid nitrogen 77 K soon followed. Today numerous high-temperature superconducting HTS cuprate phases have been uncovered with transition temperatures as high as 135 K. Many of these materials have been synthesized as epitaxial thin films. A fundamental understanding of both the superconducting properties as well as the materials science of these complex oxide materials is still emerging. Although much is known about the synthesis and properties of HTS films there remain significant challenges in this area particularly in producing thin-film materials suitable for HTS technologies. Potential applications involving HTS films include high-frequency electronics for radio-frequency RF microwave communications superconducting quantum interference devices SQUIDs for the detection of minute magnetic fields and superconducting wires for energy-efficient delivery and use of electrical energy. This chapter provides an overview of the science and technology of HTS thin-film synthesis focusing on the growth of epitaxial films. Copyright 2003 by Marcel Dekker Inc. All Rights Reserved. In order to address the materials-related issues most relevant for HTS cuprate thin films one must first discuss the generic structure for these materials. The layered crystal structure inherent to the HTS compounds yields highly anisotropic materials in terms of both the electronic properties and crystal-growth characteristics. A comprehensive overview of the various multielement crystal structures for HTS cuprates has been given elsewhere 2 . A unit cell that is .