Author Affiliations
Abstract
1 Northwestern Polytechnical University, School of Physical Science and Technology, Key Laboratory of Light Field Manipulation and Information Acquisition, Ministry of Industry and Information Technology, Shaanxi Key Laboratory of Optical Information Technology, Xi’an, China, 710129
2 Nanjing University of Posts and Telecommunications, College of Electronic and Optical Engineering & College of Microelectronics, Nanjing, China, 210046
3 Aalto University, Department of Electronics and Nanoengineering and QTF Centre of Excellence, Aalto, Finland
Chirp-free solitons have been mainly achieved with anomalous-dispersion fiber lasers by the balance of dispersive and nonlinear effects, and the single-pulse energy is constrained within a relatively small range. Here, we report a class of chirp-free pulse in normal-dispersion erbium-doped fiber lasers, termed birefringence-managed soliton, in which the birefringence-related phase-matching effect dominates the soliton evolution. Controllable harmonic mode locking from 5 order to 85 order is obtained at the same pump level of ~10 mW with soliton energy fully tunable beyond ten times, which indicates a new birefringence-related soliton energy law, which fundamentally differs from the conventional soliton energy theorem. The unique transformation behavior between birefringence-managed solitons and dissipative solitons is directly visualized via the single-shot spectroscopy. The results demonstrate a novel approach of engineering fiber birefringence to create energy-tunable chirp-free solitons in normal-dispersion regime and open new research directions in fields of optical solitons, ultrafast lasers, and their applications.
Ultrafast Science
2022, 2(1): 9760631
光子学报
2022, 51(10): 1014004
Author Affiliations
Abstract
1 Key Laboratory of Space Applied Physics and Chemistry, Ministry of Education, and Shaanxi Key Laboratory of Optical Information Technology, School of Physical Science and Technology, Northwestern Polytechnical University, Xi’an 710129, China
2 State Key Laboratory of Optoelectronic Materials & Technologies, School of Physics, Sun Yat-sen University, Guangzhou 510275, China
3 Department of Electronics and Nanoengineering, Aalto University, Espoo FI-00076, Finland
4 QTF Centre of Excellence, Department of Applied Physics, Aalto University, Espoo FI-00076, Finland
5 e-mail: jlzhao@nwpu.edu.cn
We report an indium phosphide nanowire (NW)-induced cavity in a silicon planar photonic crystal (PPC) waveguide to improve the light–NW coupling. The integration of NW shifts the transmission band of the PPC waveguide into the mode gap of the bare waveguide, which gives rise to a microcavity located on the NW section. Resonant modes with factors exceeding are obtained. Leveraging on the high density of the electric field in the microcavity, the light–NW interaction is enhanced strongly for efficient nonlinear frequency conversion. Second-harmonic generation and sum-frequency generation in the NW are realized with a continuous-wave pump laser in a power level of tens of microwatts, showing a cavity-enhancement factor of 112. The hybrid integration structure of NW-PPC waveguide and the self-formed microcavity not only opens a simple strategy to effectively enhance light–NW interactions, but also provides a compact platform to construct NW-based on-chip active devices.
Photonics Research
2020, 8(11): 11001734
Author Affiliations
Abstract
1 MOE Key Laboratory of Material Physics and Chemistry under Extraordinary Conditions, and Shaanxi Key Laboratory of Optical Information Technology, School of Science, Northwestern Polytechnical University, Xi’an 710072, China
2 Qian Xuesen Laboratory of Space Technology, China Academy of Space Technology, Beijing 100094, China
3 Department of Electronics and Nanoengineering, Aalto University, Espoo, FI-00076, Finland
4 QTF Centre of Excellence, Department of Applied Physics, Aalto University, Espoo, FI-00076, Finland
The position-dependent mode couplings between a semiconductor nanowire (NW) and a planar photonic crystal (PPC) nanocavity are studied. By scanning an NW across a PPC nanocavity along the hexagonal lattice’s Γ – M and M – K directions, the variations of resonant wavelengths, quality factors, and mode volumes in both fundamental and second-order resonant modes are calculated, implying optimal configurations for strong mode-NW couplings and light-NW interactions. For the fundamental (second-order) resonant mode, scanning an NW along the M – K (Γ – M) direction is preferred, which supports stronger light-NW interactions with larger NW-position tolerances and higher quality factors simultaneously. The simulation results are confirmed experimentally with good agreements.
230.5298 Photonic crystals 160.4236 Nanomaterials 260.5740 Resonance Chinese Optics Letters
2019, 17(6): 062301
Author Affiliations
Abstract
1 Collaborative Innovation Center for Optoelectronic Science & Technology, International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education, College of Optoelectronic Engineering, Shenzhen 518060, China
2 Department of Materials Science and Engineering, Monash University, Clayton, Victoria 3800, Australia
3 Department of Electronics and Nanoengineering, QTF Centre of Excellence, Aalto University, Tietotie, Finland
4 e-mail: hzhang@szu.edu.cn
5 e-mail: qiaoliang.bao@monash.edu
6 e-mail: zhipei.sun@aalto.fi
We introduce the background and motivation of this feature issue of two-dimensional layered materials for ultrafast lasers. A brief summary of the seven collected articles in this feature issue is also given.
Ultrafast lasers Nonlinear optics, materials Modulators Photonics Research
2018, 6(10): 1000TDL1
Author Affiliations
Abstract
1 SZU-NUS Collaborative Innovation Centre for Optoelectronic Science & Technology, Shenzhen University,
Shenzhen 518060, China
2 Department of Micro-and Nanosciences, Aalto University, PO Box 13500, FI-00076 Aalto, Finland
3 Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
We propose and demonstrate a dual-wavelength single-longitudinal-mode (SLM) fiber laser with switchable wavelength spacing based on a graphene saturable absorber (GSA) and a WaveShaper. By virtue of the excellent saturable absorption ability of graphene, the linewidths of the lasing wavelengths can be effectively reduced and eventually SLM operation can be obtained. The linewidths of both wavelengths are measured to be narrower than 7.3 kHz. The obtained results suggest that the graphene would be a good candidate nonlinear optical material for applications in related photonic fields, such as SLM oscillation generation for microwave generation and optical sensing.
Lasers Lasers fiber fiber Lasers Lasers single-mode single-mode Nonlinear optical materials Nonlinear optical materials Photonics Research
2015, 3(2): 020PBTD1
