image: The influence of SnS2 material thickness change on the nonlinearity of the device and the performance of the corresponding laser. view more
Credit: OEA
In a new publication from Opto-Electronic Advances; DOI 10.29026/oea.2021.200029 , Wenjun Liu, Beijing University of Posts and Telecommunications, Zhiyi Wei, Institute of Physics of the Chinese Academy of Sciences and Wei Guo, Beijing University of Technology, discuss nonlinear fundamental research of novel photonic devices with thickness control.
Fiber lasers are widely used in the fields of optical communications, medical surgery, laser processing and lidar due to their advantages of good beam quality, compact structure, low cost and good compatibility. Therefore, they are considered to be one of the lasers with broad application prospects. On the other hand, with the further development of nanomaterial technology, two-dimensional materials with strong nonlinearity and fast relaxation process have gradually attracted widespread attention. So far, some two-dimensional materials have been successfully applied to fiber lasers as saturable absorbers and achieved ultrashort pulses.
However, the results show that the photoelectric properties of most two-dimensional materials are sensitive to the change of thickness. Materials of the same type with different thickness often show great differences in the band gap structure and carrier relaxation. Since the saturable absorber based on two-dimensional materials is an important photonic device that controls the output in lasers, the research and effective control of the properties of the saturable absorber inevitably become a breakthrough in the development of high-performance lasers. At present, most of the current hotspots focus on the preparation of materials and the development of new materials. Research on the thickness-related optical nonlinearity of two-dimensional materials is lacking. Therefore, it has important research significance to realize the nonlinear control of saturable absorber by changing the thickness.
In response to the above-mentioned problems, the research group of Professor Wenjun Liu from Beijing University of Posts and Telecommunications, cooperated with Professor Zhiyi Wei from the Institute of Physics of the Chinese Academy of Sciences and Professor Wei Guo from Beijing University of Technology, to systematically study the nonlinear control of the saturable absorber and the influence on the corresponding laser from both theoretical and experimental aspects. The researchers selected SnS2 material to prepare the saturable absorbers and have obtained photonic devices with different modulation depth by adjusting their thickness. Further analysis of the influence of different SnS2 saturable absorbers on the stability, output power, starting threshold and pulse duration of the laser has been made by building the Q-switched lasers based on different SnS2 saturable absorbers. In addition, the authors have theoretically calculated the influence of material thickness changes on its carrier mobility and band gap structure and have revealed the inherent reasons for the nonlinearity and absorption of saturable absorbers that vary with material thickness.
Relevant research can not only effectively realize the nonlinear control of saturable absorber, offer technical reference for the subsequent engineering design of new nonlinear photonic devices, but also provide the possibility for the development of high-performance fiber lasers. It is of great significance to further develop the industrial applications of photonic devices and lasers.
Article reference: Liu ML, Wu HB, Liu XM, Wang YR, Lei M et al. Optical properties and applications of SnS2 SAs with different thickness. Opto-Electron Adv 4, 200029 (2021) . doi: 10.29026/oea.2021.200029
Keywords: nonlinear optical materials / fiber laser / Q-switching
# # # # # #
The research group of Professor Wenjun Liu of Beijing University of Posts and Telecommunications, Beijing, China has been engaged in the generation and application of femtosecond fiber laser for many years. Focusing on the key scientific issue of "effective control of nonlinear effects and application of fiber laser", the team is committed to improving the performance of fiber lasers through the introduction of new structures, new mechanisms and new methods, supporting the development of high-precision detection equipment, and serving the national scientific devices. They have published more than 100 academic papers in OL, OE, PR and other optical journals, among which more than 20 are ESI highly cited papers and more than 10 ESI hot papers. Professor Wenjun Liu has more than 4000 non-self-citations and an h-index of 41. He won the Youth Top-Notch Talent of Beijing "High-tech Innovation Program" (2017), the second prize of Optical Science and Technology Award of The Chinese Optical Society (2020), the first prize of Science and Technology Award of Chinese Materials Research Society (2020), China Top Cited Author Award of Institute of Physics (IOP) (2019, 2020) and the 100 most influential academic papers in China (2019) amongst other awards.
# # # # # #
Opto-Electronic Advances (OEA) is a high-impact, open access, peer reviewed monthly SCI journal with an impact factor of 9.682 (Journals Citation Reports for IF 2020). Since its launch in March 2018, OEA has been indexed in SCI, EI, DOAJ, Scopus, CA and ICI databases over the time and expanded its Editorial Board to 33 members from 17 countries and regions (average h-index 46).
The journal is published by The Institute of Optics and Electronics, Chinese Academy of Sciences, aiming at providing a platform for researchers, academicians, professionals, practitioners, and students to impart and share knowledge in the form of high quality empirical and theoretical research papers covering the topics of optics, photonics and optoelectronics.
# # # # # #
More information: http://www.oejournal.org/oea
Editorial Board: http://www.oejournal.org/oea/editorialboard/list
All issues available in the online archive (http://www.oejournal.org/oea/archive).
Submissions to OEA may be made using ScholarOne (https://mc03.manuscriptcentral.com/oea).
ISSN: 2096-4579
CN: 51-1781/TN
Contact Us: oea@ioe.ac.cn
Twitter: @OptoElectronAdv (https://twitter.com/OptoElectronAdv?lang=en)
WeChat: OE_Journal
# # # #