You are here

TERAHERTZ RADIATION FROM HIGH-TEMPERATURE SUPERCONDUCTING BSCCO MESAS OF VARIOUS GEOMETRIES

Download pdf | Full Screen View

Date Issued:
2015
Abstract/Description:
The purpose of this thesis is to examine the radiation from high-temperature superconducting mesas of Bi2Sr2CaCu2O8+d (BSCCO). This is motivated by the need for coherent sources of continuous wave terahertz (THz) emission capable of radiating practically in the THz frequency band. As BSCCO has been shown to be tunable from 0.5-2.4 THz (i.e., through the entire so-called terahertz gap centered about 1 THz), and has a higher peak operating temperature near 1 THz than most alternative sources, it is a good candidate for imaging and spectroscopy device applications. When a static DC voltage is applied to a BSCCO mesa, the stack of Josephson junctions intrinsic to this type-II layered superconductor synchronously radiate. Adjustment of the bath temperature and applied voltage allows for the high degree of tunability observed for such an emitter. To determine the angular dependence of radiation from BSCCO mesas, the dual source model from antenna theory is employed, and Love's equivalence principle is used to simplify this framework. The total emission power obtained in this manner for the pie-shaped wedge is then fit to experimental results for a thin isosceles triangular mesa using the method of least squares, resulting in a standard deviation of 0.4657. Additionally, symmetry is shown to play a significant role in the emissions for the transverse magnetic (TM) cavity modes of the equilateral triangular mesa. When the full group symmetry is imposed, the density of allowed modes is heavily diminished, and the original first excited even mode becomes the C3v symmetric ground state. These results for the equilateral triangle suggest, along with earlier experiments on the regular pentagonal mesa, that symmetry breaking effects can be used for purposes of tuning the characteristic frequency and angular dependence of the power radiated from BSCCO mesas with a high degree of symmetry.
Title: TERAHERTZ RADIATION FROM HIGH-TEMPERATURE SUPERCONDUCTING BSCCO MESAS OF VARIOUS GEOMETRIES.
17 views
8 downloads
Name(s): Cerkoney, Daniel, Author
Klemm, Richard, Committee Chair
University of Central Florida, Degree Grantor
Type of Resource: text
Date Issued: 2015
Publisher: University of Central Florida
Language(s): English
Abstract/Description: The purpose of this thesis is to examine the radiation from high-temperature superconducting mesas of Bi2Sr2CaCu2O8+d (BSCCO). This is motivated by the need for coherent sources of continuous wave terahertz (THz) emission capable of radiating practically in the THz frequency band. As BSCCO has been shown to be tunable from 0.5-2.4 THz (i.e., through the entire so-called terahertz gap centered about 1 THz), and has a higher peak operating temperature near 1 THz than most alternative sources, it is a good candidate for imaging and spectroscopy device applications. When a static DC voltage is applied to a BSCCO mesa, the stack of Josephson junctions intrinsic to this type-II layered superconductor synchronously radiate. Adjustment of the bath temperature and applied voltage allows for the high degree of tunability observed for such an emitter. To determine the angular dependence of radiation from BSCCO mesas, the dual source model from antenna theory is employed, and Love's equivalence principle is used to simplify this framework. The total emission power obtained in this manner for the pie-shaped wedge is then fit to experimental results for a thin isosceles triangular mesa using the method of least squares, resulting in a standard deviation of 0.4657. Additionally, symmetry is shown to play a significant role in the emissions for the transverse magnetic (TM) cavity modes of the equilateral triangular mesa. When the full group symmetry is imposed, the density of allowed modes is heavily diminished, and the original first excited even mode becomes the C3v symmetric ground state. These results for the equilateral triangle suggest, along with earlier experiments on the regular pentagonal mesa, that symmetry breaking effects can be used for purposes of tuning the characteristic frequency and angular dependence of the power radiated from BSCCO mesas with a high degree of symmetry.
Identifier: CFH0004898 (IID), ucf:45429 (fedora)
Note(s): 2015-12-01
B.S.
Sciences, Dept. of Physics
Bachelors
This record was generated from author submitted information.
Subject(s): Terahertz
Radiation
High-temperature
Superconductor
BSCCO
Persistent Link to This Record: http://purl.flvc.org/ucf/fd/CFH0004898
Restrictions on Access: public
Host Institution: UCF

In Collections