Press release -
A new chapter for nonlinear optics
A new bidimensional semiconductor shows the highest nonlinear optical efficiency over nanometer thicknesses. This is the result of a new study recently published in Nature Photonics by Xinyi Xu, PhD student of Columbia University, and Chiara Trovatello, postdoctoral research scientist at the Physics Department of Politecnico di Milano, together with Prof. Giulio Cerullo from the Physics Department of Politecnico di Milano, Dmitri N. Basov and P. James Schuck from the Columbia University of New York City (USA).
“Optical fibers, bar code readers, light scalpels for precision surgery… the innumerable applications which have revolutionized our daily life rely exclusively on one tool: the laser. Each laser, however, emits light only at one specific wavelength and in order to generate new colors one can make use of specific crystals exploiting nonlinear optical processes. The miniaturizationtrend, which has dominated the world of electronics, enabling the realization of powerful consumer devices, such as smartphones and tablets, is now moving the world of lasers and their applications, which constitute the so-called field of photonics. For this reason, it is necessary to realize nonlinear processes inside thinner and thinner crystals" - tells Chiara Trovatello, author of the study."The typical nonlinear crystal thickness is on the order of a millimiter. In this study we have proven that a new nonlinear material – the 3R crystal phase of molybdenum disulfide – over a thickness of few hundreds of nanometers (1 nm = 10-9 m) can achieve an unprecedent nonlinear optical gain. This study sets the ground for a new revolution in the field on nonlinear optics.”
This new crystal opens innumerable future applications, which could be directly integrated on a micrometric optical chip, reducing the typical size of nonlinear optical devices. Among the most relevant applications: optical amplifiers, tunable lasers and quantum light generators over nanometer length scales.
“On-chip nonlinear application will reinvent photonic devices through thinner and more compact designs. This is thanks to fundamental research, which allows us to get one step closer to the future of science and technology” concludes Prof. Cerullo.
Politecnico di Milano is a scientific-technological university which trains engineers, architects and industrial designers.
The University has always focused on the quality and innovation of its teaching and research, developing a fruitful relationship with business and productive world by means of experimental research and technological transfer.
Research has always been linked to didactics and it is a priority commitment which has allowed Politecnico Milano to achieve high quality results at an international level as to join the university to the business world. Research constitutes a parallel path to that formed by cooperation and alliances with the industrial system.
Knowing the world in which you are going to work is a vital requirement for training students. By referring back to the needs of the industrial world and public administration, research is facilitated in following new paths and dealing with the need for constant and rapid innovation. The alliance with the industrial world, in many cases favored by Fondazione Politecnico and by consortiums to which Politecnico belong, allows the university to follow the vocation of the territories in which it operates and to be a stimulus for their development.
The challenge which is being met today projects this tradition which is strongly rooted in the territory beyond the borders of the country, in a relationship which is developing first of all at the European level with the objective of contributing to the creation of a single professional training market. Politecnico takes part in several research, sites and training projects collaborating with the most qualified European universities. Politecnico's contribution is increasingly being extended to other countries: from North America to Southeast Asia to Eastern Europe. Today the drive to internationalization sees Politecnico Milano taking part into the European and world network of leading technical universities and it offers several courses beside many which are entirely taught in English.