Atom-field interactions near optical interfaces have a wide range of applications in quantum technology. Motivated by this, this paper revisits the spontaneous emission of atomic dipoles in the presence of a two sided semi-transparent mirror. First we review the main properties of the quantised electromagnetic field near a semitransparent mirror. To do so, we employ a quantum mirror image detector method which maps the experimental setup which we consider here onto analogous free space scenarios. We emphasise that the local density of states of the electromagnetic field depends on the reflection rates of both sides of the mirror surface. Hence it is not surprising that also the spontaneous decay rate of an atomic dipole in front of a semi-transparent mirror depends on both reflectance rates. Although the effect which we describe here only holds for relatively short atom-mirror distances, it can aid the design of novel photonics devices.
Optical technologies are increasingly considered for use in high-performance electronic systems to overcome the performance bottleneck of electrical interconnects when operating at high frequencies and provide high-speed communication between electronic chips and modules. Polymer waveguides are leading candidates for implementing board-level optical interconnections as they exhibit favourable mechanical, thermal and optical properties for direct integration onto conventional printed circuit boards (PCBs). Numerous system demonstrators have been reported in recent years featuring different types of polymer materials and opto-electronic (OE) PCB designs. However, all demonstrated polymer-based interconnection technologies are currently passive, which limits the length of the on-board links and the number of components that can be connected in optical bus architectures. In this paper therefore, we present work towards the formation of low-cost optical waveguide amplifiers that can be readily integrated onto standard PCBs by combining two promising optical technologies: siloxane-based polymers and ultra-fast laser plasma implantation (ULPI). Siloxane-based waveguides exhibit high-temperature resistance in excess of 300°C and low loss at different wavelength ranges, while ULPI has been demonstrated to produce very high dopant concentrations in glass thin films with values of 1.63×1021 cm−3 recently reported in Er-doped silica layers. Here we present detailed simulation studies that demonstrate the potential to achieve a internal gain of up to 8 dB/cm from such structures and report on initial experimental work on Er-doped films and waveguides demonstrating photoluminescence and good lifetimes.
Glass and polymer interstacked superlattice like nanolayers were fabricated by nanosecond-pulsed laser deposition with a 193-nm-ultraviolet laser. The individual layer thickness of this highly transparent thin film could be scaled down to 2 nm, proving a near atomic scale deposition of complex multilayered optical and electronic materials. The layers were selectively doped with Er 3+ and Eu 3+ ions, making it optically active and targeted for integrated sensor application.
We present an overview of rare-earth doped heavy metal oxide and oxy-fluoride glasses which show promise as host
materials for lasers operating in the 2-5 μm spectral region for medical, military and sensing applications. By
engineering glass composition and purity, tellurite and germanate glasses can support transmission up to and beyond 5
μm and can have favourable thermal, mechanical and environmental stability compared to fluoride glasses. We discuss
techniques for glass purification and water removal for enhanced infrared transmission. By comparing the material
properties of the glass, and spectroscopic performance of selected rare-earth dopant ions we can identify promising
compositions for fibre and bulk lasers in the mid-infrared. Tellurite glass has recently been demonstrated to be a suitable
host material for efficient and compact lasers in the ~2 μm spectral region in fibre and bulk form and the next challenge
is to extend the operating range further into the infrared region where silica fibre is not sufficiently transparent, and
provide an alternative to fluoride glass and fibre.