Phase conjugation and negative refraction using nonlinear active metamaterials.
We present an experimental demonstration of phase conjugation using nonlinear metamaterial elements. Active split-ring resonators loaded with varactor diodes are demonstrated theoretically to act as phase-conjugating or time-reversing discrete elements when parametrically pumped and illuminated with appropriate frequencies. The metamaterial elements were fabricated and shown experimentally to produce a time-reversed signal. Measurements confirm that a discrete array of phase-conjugating elements act as a negatively refracting time-reversal rf lens only 0.12λ thick.
Katko
Alexander R
AR
Department of Electrical and Computer Engineering and Center for Metamaterials and Integrated Plasmonics, Duke University, Durham, North Carolina 27708, USA.
Gu
Shi
S
Barrett
John P
JP
Popa
Bogdan-Ioan
BI
Shvets
Gennady
G
Cummer
Steven A
SA