Perovskites are materials that share a crystal structure similar to the mineral called perovskite, which consists of calcium titanium oxide (CaTiO3).
Depending on which atoms/molecules are used in the structure, perovskites can possess an impressive array of interesting properties including superconductivity, ferroelectricity, charge ordering, spin dependent transport and much more. Perovskites therefore hold exciting opportunities for physicists, chemists and material scientists.
Lasers are devices that stimulate atoms or molecules to emit light at particular wavelengths and amplify that light, typically producing a very narrow beam of radiation. The emission usually focuses on an extremely limited range of visible, infrared, or ultraviolet wavelengths.Laser is an acronym for “light amplification by the stimulated emission of radiation”. Lasers are used in extremely diverse industries and applications, like optical disk drives, laser printers, barcode scanners, DNA sequencing instruments, fiber-optics, laser surgery and other medical applications, military and law enforcement devices and much more.
As direct bandgap semiconductors, perovskites exhibit the unique optical properties of bandgap tunability, charge-carrier mobility, defect tolerance, photoluminescence quantum efficiency and power conversion efficiency. These properties make them promising light-emitting materials for high optical gain, low-threshold and multicolor laser applications. The fact that they can be fabricated from low-cost precursors via simple processes makes them attractive as well.
Lower dimensionality perovskite materials, like nanoplatelets, dots, disks, wires etc., can be tailored to be highly desirable for controlled lasing because of their optical cavities and feedback architectures.
Despite their promising features, there are several challenges, for example low exciton binding energy, environmental stability, and formation of trap states at the vicinity of grain interfaces, that need to be addressed when considering perovskite use in lasers. In that respect, 2D perovskites and triple/mixed cation perovskites appear to have potential.
The latest Perovskite lasers news:
A research team from the Shanghai Institute of Optics and Fine Mechanics has recently demonstrated perovskite CQDs (colloidal quantum dots) single-mode laser with good performance across the entire visible spectra range.
In this study, a composited microcavity was obtained through the conformal deposition of cesium lead halide perovskite (LHP) CQDs on a high quality individual sub-micron ZnO rod by dip-coating self-assembled techniques. A single-mode lasing with high quality factor and low threshold was obtained.
An international team of researchers led by Kyushu University and Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, has demonstrated stable, continuous lasing at room temperature for over an hour perovskite materials by managing to overcome a phenomenon that has so far prevented such long operation.
Recent developments in perovskite research have made them attractive for lasers because they can be fabricated from solution at low cost to have tunable colors and excellent stability, but a phenomenon termed lasing death causes lasing under constant operation at room temperature to stop after a few minutes for reasons that have been unclear.
An international team of researchers has announced the development of the world's most compact perovskite-based semiconductor laser that works in the visible range at room temperature. According to the authors of the research, the laser is a nanoparticle of only 310 nanometers in size (which is 3,000 times less than a millimeter) that can produce green coherent light at room temperature.
The scientists succeeded in exploiting the green part of the visible band, which was considered problematic for nanolasers. "In the modern field of light-emitting semiconductors, there is the 'green gap' problem," says Sergey Makarov, principal investigator of the article and professor at the Faculty of Physics and Engineering of ITMO University. "The green gap means that the quantum efficiency of conventional semiconductor materials used for light-emitting diodes falls dramatically in the green part of the spectrum. This problem complicates the development of room temperature nanolasers made of conventional semiconductor materials."
An all-inorganic perovskite micro/nano-structure has been demonstrated by a collaborative team of researchers from Shanghai Institute of Optics and Fine Mechanics of the Chinese Academy of Sciences (CAS), Shanghai Institute of Technical Physics of CAS and Nanjing Xiaozhuang University, that is believed to be a promising candidate for achieving high-performance nano-lasers.
Semiconductor nano-lasers with high spectral purity and stability, namely single-mode nano-lasers, are very desirable in color laser display, on-chip optical communication and computing. To date, most of reported nano-lasers exhibit multi-mode structure resulting from in-homogeneous gain saturation, while the realization of high-quality single-mode laser is very challenging and is largely limited by the cavity structure and the properties of the gain medium.
Israeli-German researchers demonstrate continuous lasing action in devices made from perovskite materials
A collaborative study between Tel Aviv University (TAU) in Israel and Karlsruhe Institute of Technology (KIT) in Germany demonstrates remarkable continuous lasing action in devices made from perovskites.
"In contrast to previous studies around the world, this is the first study to exhibit continuous lasing action, as opposed to pulsed operation," says Prof. Jacob Scheuer of TAU's Department of Physical Electronics, who led the TAU team of researchers. "This family of materials is considered the most promising candidate for a future laser-based industry, because their fabrication is simple, fast and inexpensive compared to current semiconductor materials being used for these purposes. In addition, these materials can support the realization of solid-state lasers emitting in green, necessary for future lighting, displays and projectors," Prof. Scheuer adds. "Current semiconductor lasers emit light only in red and blue."