Cavity mode enhancement of terahertz emission from equilateral triangular microstrip antennas of the high-$T_c$ superconductor Bi$_2$Sr$_2$CaCu$_2$O$_{8 + δ}$

Change log
Cerkoney, DP 
Reid, C 
Doty, CM 
Gramajo, A 
Campbell, TD 

We study the transverse magnetic (TM) electromagnetic cavity mode wave functions for an ideal equilateral triangular microstrip antenna (MSA) exhibiting C3v point group symmetry. When the C3v operations are imposed upon the antenna, the TM(m,n) modes with wave vectors αm2+nm+n2 are much less dense than commonly thought. The R3 operations restrict the integral n and m to satisfy mn = 3p, where p 0 and p 1 for the modes even and odd under reflections about the three mirror planes, respectively. We calculate the forms of representative wave functions and the angular dependence of the output power when these modes are excited by the uniform and non-uniform ac Josephson current sources in thin, ideally equilateral triangular MSAs employing the intrinsic Josephson junctions in the high transition temperature Tc superconductor Bi2Sr2CaCu2O8+δ, and fit the emissions data from an earlier sample for which the C3v symmetry was apparently broken.

intrinsic Josephson junctions, microstrip antennas, terahertz radiation, high temperature superconductor, equilateral triangular wave functions
Journal Title
Journal of Physics: Condensed Matter
Conference Name
Journal ISSN
Volume Title
Institute of Physics Publishing
UCF RAMP program, JSPS Research Fellowship for young scientists, CREST-JST (Japan Science and Technology Agency), WPI (World Premier International Research Center Initiative)- MANA (Materials Nanoarchitectonics) project (NIMS)