LMI Seminar: Optical Superoscillations: How we learned bypassing the bandwidth limit and experiment all night long

Abstract:

Superoscillation [1-3] is an interference phenomena in which a band limited signal oscillates locally faster than the highest frequency component available in the spectrum.In my talk I will show several works, involving both theory and experiments, which demonstrate the application of superoscillations in both spatial optics (considering beams of light) and temporal optics (considering optical pulses). I will begin by showing how superoscillation can be used to deliver an optical temporal signal through a dielectric medium even though the signal contains local oscillations matching an absorbing resonance of the medium. We term this special pulse-delivery phenomenon "super-transmission" [4]  .Next I will demonstrate how superoscillation can be harnessed in the time domain to achieve temporal super-resolution for detecting temporal events. [5], I would also show a simple and robust technique to achieve structured superoscillatory femtosecond pulses [6]. In the second part of the talk I will discuss our works in the context of spatial domain optics  and demonstrate theoretically and experimentally how superoscillations can be constructed from a anharmonic basis of functions [7] and how it is possible to achieve narrow axial focusing of a beam [8] .A significant contribution that I would also discuss is the discovery and demonstration of a complementary phenomenon to superoscillation which we term as “suboscillation” [9]. Finally, if time permits, I will also address additional recent works tying the phenomena of superoscillation with quantum backflow, parity-time symmetry and orbital angular momentum. 

References:

[1] Berry M. V., 1994, 'Faster than Fourier', in 'Quantum Coherence and Reality' World Scientific, Singapore, pp 55-65.

[2] https://en.wikipedia.org/wiki/Superoscillation  

[3] N.I. Zheludev, 'What diffraction limit?', Nature Materials 7, 420 - 422 (2008) [4] Eliezer, Yaniv, and Alon Bahabad. Optics Express 22.25 (2014): 31212-31226. [5] Eliezer, Yaniv, et al. Physical review letters 119.4 (2017): 043903.  [6] Eliezer, Yaniv, et al. Optics express 26.4 (2018): 4933-4941. [7] Eliezer, Yaniv, and Alon Bahabad. ACS Photonics 3.6 (2016): 1053-1059. [8] Zacharias T., Hadad B., Bahabad A. and Eliezer, Y. (2017): 42(16), 3205-3208. [9] Eliezer, Yaniv, and Alon Bahabad. Optica 4.4 (2017): 440-446.