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arXiv · 1112.6337

Reversible modulation and ultrafast dynamics of THz resonances in strongly photoexcited metamaterials

I. Chatzakis·L. Luo·J. Wang·N-H. Shen·T. Koschny·J. Zhou·C. M. Soukoulis
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Abstract

We demonstrate an ultrafast reversible modulation of resonant terahertz (THz) response in strongly photoexcited metamaterials. The transient spectral-temporal response of the dipole transition ~1.6 THz exhibits a distinct non-monotonic variation as a function of pump fluence. The transition energy shift, strength, spectral width and density-dependent ultrafast relaxation manifest a remarkable re-emergence of the resonances after initial quenching. Our simulation, incorporating the first-order diffraction from the photoinduced transient grating, reproduces the salient features, providing a new avenue for designing nonlinear and frequency-agile THz modulators.

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I. Chatzakis, L. Luo, J. Wang, N-H. Shen, T. Koschny, J. Zhou, C. M. Soukoulis. 2011-12-29. Reversible modulation and ultrafast dynamics of THz resonances in strongly photoexcited metamaterials. https://doi.org/10.1103/physrevb.86.125110

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