• Aeschlimann, M.; Brixner, T.; Fenner, F.; Frisch, B.; Folge, P.; Hartelt, M.; Hensen, M.; Loeber, T.H.; Pfeiffer, W.; Pres, S.; Stannowski, B.: Direct imaging of photonic band-edge states in golden Vogel spirals using photoemission electron microscopy. Journal of the Optical Society of America / B 40 (2023), p. B19-B27

10.1364/JOSAB.479667
Open Access Version

Abstract:
Golden Vogel spirals, as deterministic aperiodic structures, support isotropic photonic band gaps and have inter- esting applications. Localized modes, such as band-edge states, are essential for tailored light–matter interaction. Here we report imaging of such modes using photoemission electron microscopy (PEEM). Tunable ultrashort light pulses excite them in golden Vogel spirals that were fabricated by focused-ion-beam (FIB) milling of an a-Si:H layer. The local near-field leads to electron emission, which is detected spatially resolved. The demonstration of FIB- textured a-Si:H as photonic material and the ability of mode imaging by PEEM offers means to spatiotemporally resolve mode dynamics and to perform nanospectroscopy.