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Title: Strong Metasurface–Josephson Plasma Resonance Coupling in Superconducting La 2− x Sr x CuO 4
Abstract Terahertz spectroscopy of thec‐axis Josephson plasma resonance (JPR) in high‐temperature cuprates is a powerful probe of superconductivity, providing a route to couple to and interact with the condensate. Electromagnetic coupling between metasurface arrays of split ring resonators (SRRs) and the JPR of a La2−xSrxCuO4single crystal (Tc= 32 K) is investigated. The metasurface resonance frequency (ωMM), determined by the SRR geometry, is swept through the JPR frequency (ωJPR= 1.53 THz) using a series of interchangeable tapes applied to the same single crystal. Terahertz reflectivity measurements on the resulting hybrid superconducting metamaterials (HSMMs) reveal anticrossing behavior characteristic of strong coupling. The experimental results, validated with numerical simulations, indicate a normalized Rabi frequency of ΩR= 0.29. Further, it is shown that HSMMs with ωMM> ωJPRprovide a route to couple to hyperbolic waveguide modes inc‐axis cuprate samples. This work informs future possibilities for optimizing the coupling strength of HSMMs and investigating nonlinear superconductivity under high field terahertz excitation.  more » « less
Award ID(s):
1810252
PAR ID:
10454645
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Optical Materials
Volume:
7
Issue:
21
ISSN:
2195-1071
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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