POW Seminar - Copper as a Nonlinear Platform: Stable SHG from Monocrystalline Microflakes

The EPFL Photonics Chapter (EPC) is very pleased to announce and cordially invite you to the Christmas edition of our monthly ‘Pizza-Optics-Beer’ (POB) seminar, renamed for this occasion POW (there will be mulled wine), on Tuesday December 9th, at 18:15 in room CO 122.

This month we will have the pleasure to host Elif Nur Dayi - doctoral assistant in  Laboratory of Nanoscience for Energy Technologies with the presentation entitled:

"Copper as a Nonlinear Platform: Stable SHG from Monocrystalline Microflakes"

For organizational purposes (if you want to eat pizza!), please confirm your participation using this Doodle.
Don’t hesitate to extend the invitation to any postdoc and colleague!

Hope to see you there,
The EPFL Photonics Chapter team


Abstract:
Monocrystalline copper has remained largely unexplored as a nonlinear optical material because its surface oxidizes rapidly, despite its importance in catalysis, plasmonics, and energy conversion. Here we show that oxidation-resistant Cu(111) microflakes grown through an on-substrate synthesis route enable stable and reproducible second-harmonic generation (SHG) under ambient conditions. The SHG signal remains highly stable during three hours of continuous femtosecond excitation, demonstrating remarkable photostability. Polarization-resolved measurements reveal a clear six-lobe pattern characteristic of C₃ᵥ surface symmetry, with strong cross-polarized emission when the incident field aligns with crystal axes. By contrast, polycrystalline Cu films produce weak, isotropic SHG, highlighting the role of monocrystallinity and surface order. Together, these results establish monocrystalline Cu(111) as a robust and anisotropic nonlinear optical platform, broadening copper’s potential in plasmonic and nanophotonic systems as well as in surface-specific optical studies relevant to catalysis and energy interfaces.


You don't know POBs?
POBs (Pizza-Optics-Beer) are monthly seminars organized by the student association EPFL Photonics Chapter.
A PhD or a postdoc gives a 20-minutes presentation about his/her research in photonics. Discussions continue informally around pizza and beers!
For this Christmas edition, we will have mulled wine instead, so the POB will become a POW ("Pizza-Optics-Wine").

The event is free and open to anyone.


We thank the Doctoral Program in Photonics (EPDO), the Society of Photo-Optical Instrumentation Engineers (SPIE.), Optica and SwissPhotonics for their support.