Quasi-guided modes resulting from the band folding effect in a photonic crystal slab for enhanced interactions of matters with free-space radiations

• Kaili Sun,
• Yangjian Cai,
• Uriel Levy and
• Zhanghua Han

Beilstein J. Nanotechnol. 2023, 14, 322–328, doi:10.3762/bjnano.14.27

• of Jerusalem, Jerusalem, Israel 10.3762/bjnano.14.27 Abstract We elucidate that guided modes supported by a regular photonic crystal slab structure composed of a square lattice of air holes in a silicon slab will transition into quasi-guided (leaky) modes when the radius of every second column of

• superior properties will provide a new platform for efficient light–matter interactions. Keywords: guided modes; light–matter interactions; photonic crystal slab; Introduction Photonic resonances with the possibility of free-space excitation (i.e., leaky modes) and large local electromagnetic field

• difference frequency generation (DFG) by using 1D leaky modes of binary waveguide gratings [21] and to manipulate the radiation coupling in the vertical directions in some photonic crystal cavities [22][23]. A similar structure of a ZnO photonic crystal slab (PCS) with doubled periods in both directions has

Liquid crystal tunable claddings for polymer integrated optical waveguides

• José M. Otón,
• Manuel Caño-García,
• Fernando Gordo,
• Eva Otón,
• Morten A. Geday and
• Xabier Quintana

Beilstein J. Nanotechnol. 2019, 10, 2163–2170, doi:10.3762/bjnano.10.209

• the confinement of the modes illustrated on the right of Figure 5. The top inset, corresponding to neff = 1.548, shows two leaky modes (actually they reach beyond the boundaries of the calculation). In other words, the refractive index of the cladding is too close to the refractive index of the core

Two-dimensional photonic crystals increasing vertical light emission from Si nanocrystal-rich thin layers

• Lukáš Ondič,
• Marian Varga,
• Ivan Pelant,
• Alexander Kromka,
• Karel Hruška and
• Robert G. Elliman

Beilstein J. Nanotechnol. 2018, 9, 2287–2296, doi:10.3762/bjnano.9.213

• into square and hexagonal pattern with lattice constants computed such that the red photoluminescence of Si nanocrystals (SiNCs) could couple to leaky modes of the PhCs and could be efficiently extracted to surrounding air. Samples having different lattice constants and heights of columns were

• investigated in order to find the configuration with the best performance. Spectral overlap of the leaky modes with the luminescence spectrum of SiNCs was verified experimentally by measuring photonic band diagrams of the leaky modes employing angle-resolved spectroscopy and also theoretically by computing the

• spatial collection angle of 14°. Keywords: leaky modes; photoluminescence; photonic crystals; silicon nanocrystals; Introduction Photonic and plasmonic nanostructures can be employed to manipulate light on the nanoscale [1][2][3][4]. For example, photons emitted within a thin waveguiding layer can be

Localized photodeposition of catalysts using nanophotonic resonances in silicon photocathodes

• Evgenia Kontoleta,
• Sven H. C. Askes,
• Lai-Hung Lai and
• Erik C. Garnett

Beilstein J. Nanotechnol. 2018, 9, 2097–2105, doi:10.3762/bjnano.9.198

• appearance of localized “hot spots”. In particular, semiconducting nanostructures can sustain Mie-like leaky modes due to their high refractive index and the occurrence of multiple internal light reflections from the boundaries of the structure [9][13]. However, in vertical nanowires under normal-incidence