Broad frequency shift of parametric processes in Epsilon-Near-Zero time-varying media

Vincenzo Bruno; Stefano Vezzoli; Clayton DeVault; Enrico Carnemolla; Marcello Ferrera; Alexandra Boltasseva; Vladimir M. Shalaev; Daniele Faccio; Matteo Clerici

arXiv · 1912.00052

Broad frequency shift of parametric processes in Epsilon-Near-Zero time-varying media

Vincenzo Bruno·Stefano Vezzoli·Clayton DeVault·Enrico Carnemolla·Marcello Ferrera·Alexandra Boltasseva·Vladimir M. Shalaev·Daniele Faccio·Matteo Clerici

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Abstract

The ultrafast changes of material properties induced by short laser pulses can lead to frequency shift of reflected and transmitted radiation. Recent reports highlight how such a frequency shift is enhanced in the spectral regions where the material features a near-zero real part of the permittivity. Here we investigate the frequency shift for fields generated by four-wave mixing with a nonlinear polarisation oscillating at twice the pump frequency. In our experiment we observe a frequency shift of more than 60 nm (compared to the pulse width of ~40 nm) for the phase conjugated radiation generated by a 500 nm Aluminium-doped Zinc Oxide (AZO) film pumped close to the epsilon-near-zero wavelength. Our results indicate applications of time-varying media for nonlinear optics and frequency conversion.

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Vincenzo Bruno, Stefano Vezzoli, Clayton DeVault, Enrico Carnemolla, Marcello Ferrera, Alexandra Boltasseva, Vladimir M. Shalaev, Daniele Faccio, Matteo Clerici. 2019-11-29. Broad frequency shift of parametric processes in Epsilon-Near-Zero time-varying media. https://arxiv.org/abs/1912.00052

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