This time around, nanotechnology has made its way into the realm of lighting. Researchers at the Arizona State University (ASU) have successfully created a customized semiconductor, which has led to the development of the so-called white laser – a potential lighting equivalent that is brighter and more efficient than LEDs. To that end, this bespoke semiconductor laser can account for the entire visible color spectrum, as opposed to the generation of a single wavelength of light by conventional semiconductors. In essence, this leads to the production of red, green, and blue lasers that ultimate combine to morph into the physically ‘pure’ white light.
The customized nanoscale semiconductor in question is based on an alloy of ZnCdSSe, and is segmented into three sections. The aforementioned combination of wavelengths was achieved by regulating the lattice pattern of the said material. This allowed the optimized arrangement of the lattice constant (the distance between the atoms) in the pattern, thus leading to the production of the preferred area. For example, the blue light was made to shine by utilizing nanotechnology – that led to creation of the preferred lattice, and its cuing into the right alloy composition.
Such complex arrangements within the material (with three separate lattices and compositions) were only possible due to the high quality nature of the semiconductor crystals. And as we mentioned before, the resultant laser is not only capable of producing white light, but can also be synced across the entire spectrum. So, in terms of potential applications, the white laser might just be the perfect candidate for efficient lighting of the near-future.
What’s more, according to the researchers, the laser has a whopping 70 percent greater color range that is more accurate and vibrant. So that makes a great case for televisions, computer monitors and even light based WiFi (or Li-Fi) of the future. In fact, on a theoretical level, such a laser-based WiFi system can account for ten times faster speed than conventional WiFi.
But before we get ahead of ourselves, it should be noted that the white laser was created as a proof of concept. As the ASU project page makes it clear –
While this first proof of concept is important, significant obstacles remain to make such white lasers applicable for real-life lighting or display applications. One of crucial next steps is to achieve the similar white lasers under the drive of a battery. For the present demonstration, the researchers had to use a laser light to pump electrons to emit light. This experimental effort demonstrates the key first material requirement and will lay the groundwork for the eventual white lasers under electrical operation.
The study was originally published in Nature Nanotechnology.