title: Phosphorene quantum dot saturable absorbers for ultrafast fiber lasers.
abstract: We fabricate ultrasmall phosphorene quantum dots (PQDs) with an average size of 2.6 ± 0.9 nm using a liquid exfoliation method involving ultrasound probe sonication followed by bath sonication. By coupling the as-prepared PQDs with microfiber evanescent light field, the PQD-based saturable absorber (SA) device exhibits ultrafast nonlinear saturable absorption property, with an optical modulation depth of 8.1% at the telecommunication band. With the integration of the all-fiber PQD-based SA, a continuous-wave passively mode-locked erbium-doped (Er-doped) laser cavity delivers stable, self-starting pulses with a pulse duration of 0.88 ps and at the cavity repetition rate of 5.47 MHz. Our results contribute to the growing body of work studying the nonlinear optical properties of ultrasmall PQDs that present new opportunities of this two-dimensional (2D) nanomaterial for future ultrafast photonic technologies.
authors.affiliation: School of Electronic and Information Engineering, Beihang University, Beijing, 100191, China.|Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, College of Physics and Microelectronic Science, Hunan University, Changsha 410082, China.|SZU-NUS Collaborative Innovation Centre for Optoelectronic Science &Technology, and Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, Shenzhen University, Shenzhen, China.
authors.forename: J
authors.initials: J
authors.lastname: Du
authors.affiliation: School of Electronic and Information Engineering, Beihang University, Beijing, 100191, China.|International Research Institute for Multidisciplinary Science, Beihang University, Beijing, 100191, China.
authors.forename: M
authors.initials: M
authors.lastname: Zhang
authors.affiliation: SZU-NUS Collaborative Innovation Centre for Optoelectronic Science &Technology, and Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, Shenzhen University, Shenzhen, China.
authors.forename: Z
authors.initials: Z
authors.lastname: Guo
authors.affiliation: School of Electronic and Information Engineering, Beihang University, Beijing, 100191, China.
authors.forename: J
authors.initials: J
authors.lastname: Chen
authors.affiliation: School of Electronic and Information Engineering, Beihang University, Beijing, 100191, China.
authors.forename: X
authors.initials: X
authors.lastname: Zhu
authors.affiliation: School of Electronic and Information Engineering, Beihang University, Beijing, 100191, China.
authors.forename: G
authors.initials: G
authors.lastname: Hu
authors.affiliation: International Research Institute for Multidisciplinary Science, Beihang University, Beijing, 100191, China.|School of Mechanical Engineering and Automation, Beihang University, Beijing, 100191, China.
authors.forename: P
authors.initials: P
authors.lastname: Peng
authors.affiliation: School of Electronic and Information Engineering, Beihang University, Beijing, 100191, China.|Collaborative Innovation Center of Geospatial Technology, Wuhan, 430079, China.
authors.forename: Z
authors.initials: Z
authors.lastname: Zheng
authors.affiliation: SZU-NUS Collaborative Innovation Centre for Optoelectronic Science &Technology, and Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, Shenzhen University, Shenzhen, China.
authors.forename: H
authors.initials: H
authors.lastname: Zhang