Nonlinear time reversal of classical waves: experiment and model.
We consider time reversal of electromagnetic waves in a closed, wave-chaotic system containing a discrete, passive, harmonic-generating nonlinearity. An experimental system is constructed as a time-reversal mirror, in which excitations generated by the nonlinearity are gathered, time-reversed, transmitted, and directed exclusively to the location of the nonlinearity. Here we show that such nonlinear objects can be purely passive (as opposed to the active nonlinearities used in previous work), and we develop a higher data rate exclusive communication system based on nonlinear time reversal. A model of the experimental system is developed, using a star-graph network of transmission lines, with one of the lines terminated by a model diode. The model simulates time reversal of linear and nonlinear signals, demonstrates features seen in the experimental system, and supports our interpretation of the experimental results.
Department of Physics, University of Maryland, College Park, Maryland 20742-4111, USA.
Matthew
M
Frazier
Department of Physics, University of Maryland, College Park, Maryland 20742-4111, USA and Department of Electrical and Computer Engineering, University of Maryland, College Park, Maryland 20742-3285, USA.
Biniyam
B
Taddese
Department of Physics, University of Maryland, College Park, Maryland 20742-4111, USA and Department of Electrical and Computer Engineering, University of Maryland, College Park, Maryland 20742-3285, USA.
Bo
B
Xiao
Department of Physics, University of Maryland, College Park, Maryland 20742-4111, USA and Department of Electrical and Computer Engineering, University of Maryland, College Park, Maryland 20742-3285, USA.
Thomas
T
Antonsen
Department of Physics, University of Maryland, College Park, Maryland 20742-4111, USA and Department of Electrical and Computer Engineering, University of Maryland, College Park, Maryland 20742-3285, USA.
Edward
E
Ott
Department of Physics, University of Maryland, College Park, Maryland 20742-4111, USA and Department of Electrical and Computer Engineering, University of Maryland, College Park, Maryland 20742-3285, USA.
Steven M
SM
Anlage