Interactions of low-power photons with natural opals—PBG materials, photonic control, natural metamaterials, spontaneous laser emissions, and band-gap boundary responses

One overall goal of this research was to examine types of naturally-occurring opals that exhibit photonic control to learn about previously-unknown properties of naturally occurring photonic control that may be developed for broader applications. Three different photon sources were applied consecutively to three different types of natural, flawless, gem-quality precious opals. Two photon sources were lasers (green and red) and one was simulated daylight tungsten white. As each type of precious opal was exposed to each of the photon sources, the respective refractions, reflections, and transmissions were studied. This research is the first to show that applying various pleochroic and laser photon sources to these types of opals revealed significant information regarding naturally occurring photonic control, metamaterials, spontaneous laser emissions, and microspheroid cluster (inter-PBG zone) boundary effects. Plus, minimizing ambient light and the use of low power photon sources were critical to observing the properties regarding this photonic materials research. This research yielded information applicable to the development of materials to advance applications and devices of photonics, phononics, optoelectronics, nanomaterials, and metamaterials.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideFour views of each of the opal research specimens in white light (for in-article or cover), in the same order as the specimens depicted in Fig. 3 of the main manuscript.A.On the left: 1.5 carat oval cabochon precious fire opal.B.In the center: 2.5 carats faceted fancy shield precious fire contra luz with mild adularescence.C.On the right: 5.0 carats round cabochon precious crystal opal with blue adularescence.Highlights► Emission of micro-lasers from microspheroid cluster boundary zones (quantum dots). ► Lasers illuminated or fluoresced the intra-opal structures of microspheroid photonic glass clusters. ► Microspheroid boundaries are durable to low power light sources. ► Display of previously unknown low power photonic optic properties. ► The research specimens are natural metamaterials.