Related papers: The Effect of Defect Layer on Lasing in Cholesteri…
We show that the mechanical effect of light on the orientational ordering of the crystalline axis of a mesophase can be used to control the dynamics of the optical response of liquid crystal infiltrated photonic structures. The…
Plasmonic crystals are well known to have band structure including a bandgap, enabling the control of surface plasmon propagation and confinement. The band dispersion relation of bulk crystals has been generally measured by…
The photonic local density of states (PLDOS) determines the light matter interaction strength in nanophotonic devices. For standard dielectric devices, the PLDOS is fundamentally limited by diffraction, but its precise dependence on the…
Delivering a well defined state of polarization over hollow core fibres (HCFs) is pivotal for next generation ultra stable photonic systems. Yet in all existing HCFs, whether birefringent or not, their polarization extinction ratio (PER)…
Large and persistent photoconductivity (LPPC) in semiconductors is due to the trapping of photo-generated minority carriers at crystal defects. Theory has suggested that anion vacancies in II-VI semiconductors are responsible for LPPC due…
We studied numerically and experimentally the effects of structural disorder on the performance of ultraviolet photonic crystal slab lasers. Optical gain selectively amplifies the high-quality modes of the passive system. For these modes,…
We study the electrode polarization behaviour of different Na-Ca-phosphosilicate glasses by measuring the differential capacitance between blocking Pt electrodes. At low applied dc bias voltages, we detect a linear capacitance regime with…
The photonic density of states (PDOS), like its' electronic coun- terpart, is one of the key physical quantities governing a variety of phenom- ena and hence PDOS manipulation is the route to new photonic devices. The PDOS is conventionally…
A deep understanding of defects is essential for the optimisation of materials for solar energy conversion. This is particularly true for metal oxide photo(electro)catalysts, which typically feature high concentrations of charged point…
In this paper, the characteristic matrix method is employed to theoretically investigate the propagation of electromagnetic waves through one-dimensional defective lossy photonic crystals (PCs) composed of negative index materials (NIMs)…
Nonlinear optical propagation in cholesteric liquid crystals (CLC) with a spatially periodic helical molecular structure is studied experimentally and modeled numerically. This periodic structure can be seen as a Bragg grating with a…
Liquid crystals (LCs) form an extremely rich range of self-assembled topological structures with artificially or naturally created topological defects. Some of the main applications of LCs are various optical and photonic devices, where…
Based on a modified Ising model in a transverse field we demonstrate that defect layers in ferroelectric thin films, such as layers with impurities, vacancies or dislocations, are able to induce a strong increase or decrease of the…
Precise control over the electronic and optical properties of defect centers in solid-state materials is necessary for their applications as quantum sensors, transducers, memories, and emitters. In this study, we demonstrate, from first…
The simultaneous existence of coherent perfect absorption (CPA) and lasing is one of the most intriguing features of non-Hermitian photonics. However, the link between CPA lasing and PT symmetry breaking at the exceptional point (EP) needs…
We report here investigations on the instability in luminescence of bare (TOPO-stabilized) and CdS- capped CdSe particles under infrared radiation. During photo-thermal annealing the formation of oxide layers on the surfaces of the…
Azo-dye-doped liquid crystal elastomers (LCEs) are known to show a strong photomechanical response. We report on experiments that suggest that photothermal heating is the underlying mechanism in surface-constrained geometry. In particular,…
Temperature dependent photoluminescence (PL) is used to study the electronic properties of single CdS nanowires. At low temperatures, both near-band edge (NBE) photoluminescence (PL) and spatially-localized defect-related PL are observed in…
We fabricated two dimensional photonic crystal structures in zinc oxide films with focused ion beam etching. Lasing is realized in the near ultraviolet frequency at room temperature under optical pumping. From the measurement of lasing…
In this paper, for the first time, analytical expressions for determination of the wavelength of defect modes (DMs) in one-dimensional (1D) photonic crystals (PCs) with two defect layers (DLs) were obtained from the condition of zero…