Optics and Photonics Essential Technologies for Our Nation (2013) / Chapter Skim
Currently Skimming:
9 Strategic Materials for Optics
9 Strategic Materials for Optics
Pages 248-259
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 248... ...
We have seen key optoelectronic materials play an important role in negotiations between countries. Material development has always been a slow and expensive process, but with the advent of engineered materials and the rise of awareness of the importance of certain materials, materials have taken on a strong enough strategic importance to warrant their own chapter in the present report.
|
From page 249... ...
Several of the exotic elements required by emerging solar technologies rely on joint production methods, which pose another potential risk to scale-up. These 2 The 2008 Nobel Prize in chemistry was awarded jointly to Martin Chalfie, Osamu Shimomura, and Roger Y
|
From page 250... ...
waste management derives most of its profit from processing waste to remove precious and rare metals and other substances. NOVEL STRUCTURES: SUB-WAVELENGTH OPTICS, METAMATERIALS, AND PHOTONIC CRYSTALS In addition to new core materials, there is much promise in tailoring existing materials in novel ways to produce innovative results.
|
From page 251... ...
S t r at e g i c M at e r i a l s for Optics 251 FIGURE 9.1 Location of current copper and aluminum-ore production. Energy critical elements required for several emerging solar technologies are obtained as by-products of refinement.
|
From page 252... ...
Complex PhC structures with varied dimensions have been reported; these structures allow devices to be made that can control properties such as spectral and polarization dependence in transmission, refraction, reflection, absorption, and emission of light.12,13,14 Interesting metal patterns have been added to such periodic structures to produce negative refractive index and superlens effects;15,16 these patterns can focus light below the conven tional diffraction limit. PhC devices are also being actively deployed in biosensors, semiconductor lasers, and hollow-core fibers.17,18,19,20 A new class of dielectric sub-wavelength grating exhibits very different prop 7 Yablonovitch, E
|
From page 253... ...
Researchers have designed materials that can bend visible light at unusual but precise angles, regardless of its polarization,25 as a step toward perfectly transparent solar cell coatings that would direct all the Sun's rays into the active area to improve solar power output. In addition, research ers are working on novel antireflective solar cell coatings in the hope of getting more light into the cells.26,27 Finally, metastructured materials can be used to sepa rate the solar spectrum efficiently to optimize solar energy conversion.28 The versatility of metamaterials and photonic nanostructures in tailoring optical properties could lead to radical improvements and completely new types of devices.
|
From page 254... ...
The applications of nanostructures for optoelectronic devices started when one-dimensional confinement structures, quantum wells, were demonstrated in 1974.34 Double heterostructured material with a thickness under 20 nm was shown to provide quantum confinement of electrons to alter the material's effective band gap energy. Today, most semiconductor diode lasers and integrated optoelectronics use quantum wells as a means to control wavelength, reduce threshold, and provide modulation.
|
From page 255... ...
IEEE Photonics Technology Letters 19:1631-1633.
|
From page 256... ...
Another special feature of nanostructured materials is their large surface to-volume ratio. For optoelectronic devices, that is detrimental inasmuch as the surface recombination represents dark current46 and non-radiative recombination.
|
From page 257... ...
These methods can lead to higher uniformity, but they still suffer from surface defects.58,59 OPTICAL MATERIALS IN THE LIFE SCIENCES AND SYNTHETIC BIOLOGY Synthetic biology is a new field of biological research and technology develop ment that combines science and engineering with the goal of designing and con structing novel and useful biological systems not found in nature. Synthetic biology has provided the means of both genetically engineering specific optical properties 51 Stranski, Ivan N., and Lubomir Krastanov.
|
From page 258... ...
The optical materials are a critical element in the technology that will ultimately enable the $1,000 genome, which will help to make possible a new era of personalized medicine.60 New nanostructured materials have also demonstrated new methods for label ing cells and intracellular organelles with biocompatible optical materials by us ing nano-scale semiconductor structures (QDs) and nanometer gold spheres and rods.
|
From page 259... ...
The two key rare earth materials that provide color LED lighting are europium and terbium. RECOMMENDATIONS The committee presents the following recommendations with respect to stra tegic materials for optics.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.