Mike Taverne

Northumbria University · Department of Mathematics, Physics and Electrical Engineering

Hexagonal boron nitride is rapidly gaining interest as a platform for photonic quantum technologies, due to its two-dimensional nature and its ability to host defects deep within its large band gap that may act as room-temperature single-photon emitters. In this review paper we provide an overview of (1) the structure, properties, growth and transf...

To achieve the modification of photonic band structures and realize the dispersion control toward functional photonic devices, composites of photonic crystal templates with high-refractive-index material are fabricated. A two-step process is used: 3D polymeric woodpile templates are fabricated by a direct laser writing method followed by chemical v...

We demonstrate pinpoint control over aqueous particles using optically driven hydrodynamic tweezers: dynamically engineered flow-fields created by piloting optically trapped actuators. This avoids direct illumination with lasers, and removes material constraints on trappable particles.

We study polymer photonic crystals coated with varying thickness of high refractive index material aiming to make functional photonic devices capable of controlling light through band structure and dispersion. We observed red shifts of partial bandgaps in the near infrared region when the thickness of deposited MoS₂ films increases. A ~1...

Three-dimensional nanostructured magnetic materials have recently been the topic of intense interest since they provide access to a host of new physical phenomena. Examples include new spin textures that exhibit topological protection, magnetochiral effects and novel ultrafast magnetic phenomena such as the spin-Cherenkov effect. Two-photon lithogr...

We present an inverse rod-connected diamond structure showing a complete bandgap with refractive index contrast down to nhigh/nlow ~ 1.9. The structures were fabricated using a low-temperature chemical vapor deposition process, via a single-inversion technique.

Three-dimensional complete photonic bandgap materials or photonic crystals block light propagation in all directions. The rod-connected diamond structure exhibits the largest photonic bandgap known to date and supports a complete bandgap for the lowest refractive index contrast ratio down to nhigh/nlow ∼1.9. We confirm this threshold by measuring a...

Optical tweezers are a highly versatile tool for exploration of the mesoscopic world, permitting non-contact manipulation of nanoscale objects. However, direct illumination with intense lasers restricts their use with live biological specimens, and limits the types of materials that can be trapped. Here we demonstrate an indirect optical trapping p...

For an efficient single-photon source a high-count rate into a well-defined spectral and spatial mode is desirable. Here we have developed a hybrid planar Fabry-Pérot microcavity by using a two-photon polymerization process (2PP) where coupling between single-photon sources (diamond colour centres) and resonance modes is observed. The first step co...

We show that micron-scale two-dimensional (2D) honeycomb microwells can significantly improve the stability of blue phase liquid crystals (BPLCs). Polymeric microwells made by direct laser writing improve various features of the blue phase (BP) including a dramatic extension of stable temperature range and a large increase both in reflectivity and...

We show that it is possible to confine light in a volume of order 10 − 3 cubic wavelengths using only dielectric material. Low-index (air) cavities are simulated in high-index rod-connected diamond photonic crystals. These cavities show long storage times ( Q -factors > 10 6 ) even at the lowest volumes. Fabrication of such structures could open a...

In this paper, we present a design of a three-dimensional (3D) photonic crystal (PhC) nanocavity based on an optimized woodpile structure. By carefully choosing the position of the defect at the lattice center, we can create a cavity with high symmetry which supports well confined Gaussian-like cavity modes similar to those seen in a Fabry Perot la...

The structural integrity of nuclear fission and fusion power plant components is the focus of this research. The state of the art is using micro scale specimens milled with a focussed ion beam (FIB). Because of their very low volume such specimens can be lab tested, even when irradiated to low or medium level of activity. This offers a possibility...

We propose a method to directly visualize the photonic band-structure of micrometer-sized photonic crystals using wide-angle spectroscopy. By extending Fourier imaging spectroscopy sensitivity into the infrared range, we have obtained accurate measurements of the band structures along the high-symmetry directions (X-W-K-L-U) of polymeric three-dime...

We propose a method to directly visualize the photonic band-structure of micron size photonic crystals using wide angle spectroscopy. By extending Fourier Imaging Spectroscopy sensitivity into the infrared range we have obtained accurate measurements of the band-structures along the high-symmetry directions (X-W-K-L-U) of polymeric three-dimensiona...

Defect cavities in 3D photonic crystal can trap and store light in the smallest volumes allowable in dielectric materials, enhancing non-linearities and cavity QED effects. Here, we study inverse rod-connected diamond (RCD) crystals containing point defect cavities using plane-wave expansion and finite-difference time domain methods. By optimizing...

3D printing and actively switchable redox-active oligo(aniline)-based materials are combined to create novel tuneable 3D photonic materials. By a direct laser writing process, switchable functional structures with submicrometer features are fabricated. Reversible changes in the refractive index of the written materials are generated with negligible...

We present the simulation, fabrication, and optical characterization of low-index polymeric rod-connected diamond (RCD) structures. Such complex three-dimensional photonic crystal structures are created via direct laser writing by two-photon polymerization. To our knowledge, this is the first measurement at near-infrared wavelengths, showing partia...

Rod connected diamond (RCD) [1], which is known to exhibit the largest full PBGs among all designs [2] with the same index contrast, has been investigated but remains a significant challenge to create [3]. Here, we use Direct Laser Writing [4] (DLW) method to fabricate polymeric (n = 1.52) RCD templates and characterize its band structure via an an...

We report the optical properties of single defects in inverse three-dimensional (3D) rod-connected diamond (RCD) photonic crystal (PhC) cavities by using plane-wave expansion (PWE) and finite-difference time domain (FDTD) methods. By optimizing the dimensions of a 3D inverse RCD PhC, wide photonic band gaps (PBG) are obtained. Optical cavities with...

We present a low-index polymeric three-dimensional photonic crystal, rod-connected diamond structure, created via direct laser writing, showing a partial photonic band gap at near-infrared wavelengths in both P and S polarization, measured by angular resolved Fourier image spectroscopy. We show initial tests of backfilling with high refractive inde...

We report the optimization of optical properties of single defects in three-dimensional (3D) face-centered-cubic (FCC) woodpile photonic crystal (PC) cavities by using plane-wave expansion (PWE) and finite-difference time-domain (FDTD) methods. By optimizing the dimensions of a 3D woodpile PC, wide photonic band gaps (PBG) are created. Optical cavi...

We present evidence of optical Tamm states to surface plasmon polariton (SPP) coupling. We experimentally demonstrate that for a Bragg stack with a thin metal layer on the surface, hybrid Tamm-SPP modes may be excited when a grating on the air-metal interface is introduced. Out-coupling via the grating to free space propagation is shown to enhance...

This paper presents the fabrication, simulation and measurement of low refractive index micropilar/microcavity structures where the optical properties are retrieved by white light Fourier image spectroscopy. This paper aims to show with these results that organic micropillars and low refractive index cavities in 3D photonic crystals could be a suit...

We present the modeling and simulation of 3-D face-centered cubic photonic crystal (PhC) cavities with various defects. We use the plane-wave expansion method to map the allowed modes and photonic bandgaps. Having determined the photonic bands we design specific defects and input-output waveguides and model the coupling between defects and waveguid...

We present the modeling and simulation of 3-D face-centered cubic photonic crystal (PhC) cavities with various defects. We use the plane-wave expansion method to map the allowed modes and photonic bandgaps. Having determined the photonic bands we design specific defects and input-output waveguides and model the coupling between defects and waveguid...