Solitary wave evolution of optical planar vortices in isotropie self-defoeusing photorefractive media is investigated in detail. We demonstrate that the formation of a planar vortex soliton intensively depends on the ...Solitary wave evolution of optical planar vortices in isotropie self-defoeusing photorefractive media is investigated in detail. We demonstrate that the formation of a planar vortex soliton intensively depends on the diameter and maximum intensity of the input vortex Seam. The exact solutions of planar vortex solitons are obtained due to the Petviashvili iteration method. It is found that, with the increasing soliton maximum intensity, the soliton core will be gradually diminished to a minimum value.展开更多
Graphene and other two-dimensional materials have recently emerged as promising candidates for next-generation, high-performance photonics. In this paper, the progress of research into photodetectors and other electro...Graphene and other two-dimensional materials have recently emerged as promising candidates for next-generation, high-performance photonics. In this paper, the progress of research into photodetectors and other electro-optical devices based on graphene integrated silicon photonics is briefly reviewed. We discuss the performance metrics, photo-response mechanisms, and experimental results of the latest graphene photodetectors integrated with silicon photonics, We also lay out the unavoidable performance trade-offs in meeting the requirements of various applications. In addition, we describe other opto-electronic devices based on this idea. Integrating two-dimensional materials with a silicon platform provides new opportunities in advanced integrated photonics.展开更多
We present a simple method to measure the topological charges of optical vortices with multiple singularities. Using a cylindrical lens, a vortex beam can decay into a light field distribution with multiple separated ...We present a simple method to measure the topological charges of optical vortices with multiple singularities. Using a cylindrical lens, a vortex beam can decay into a light field distribution with multiple separated dark holes, whose number just equals the topological charge of the input beam. This conclusion is then verified via experiments and numerical simulations of the propagation of vortex beams with multiple singulaxities. This method is also reliable to measure the topological charges of broadband vortex beams with different distributions of singularities, which does not resort to multiple beam interferometrie experiments.展开更多
We demonstrate a reconfigurable black phosphorus electrical field transistor,which is van der Waals heterostructured with few-layer graphene and hexagonal boron nitride flakes.Varied homojunctions could be realized by...We demonstrate a reconfigurable black phosphorus electrical field transistor,which is van der Waals heterostructured with few-layer graphene and hexagonal boron nitride flakes.Varied homojunctions could be realized by controlling both source–drain and top-gate voltages.With the spatially resolved scanning photocurrent microscopy technique,photovoltaic photocurrents originated from the band-bending regions are observed,confirming nine different configurations for each set of fixed voltages.In addition,as a phototransistor,high responsivity(～800 mA/W)and fast response speed(～230μs)are obtained from the device.The reconfigurable van der Waals heterostructured transistors may offer a promising structure towards electrically tunable black phosphorus-based optoelectronic devices.展开更多
文摘Solitary wave evolution of optical planar vortices in isotropie self-defoeusing photorefractive media is investigated in detail. We demonstrate that the formation of a planar vortex soliton intensively depends on the diameter and maximum intensity of the input vortex Seam. The exact solutions of planar vortex solitons are obtained due to the Petviashvili iteration method. It is found that, with the increasing soliton maximum intensity, the soliton core will be gradually diminished to a minimum value.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61522507 and 11404264)
文摘Graphene and other two-dimensional materials have recently emerged as promising candidates for next-generation, high-performance photonics. In this paper, the progress of research into photodetectors and other electro-optical devices based on graphene integrated silicon photonics is briefly reviewed. We discuss the performance metrics, photo-response mechanisms, and experimental results of the latest graphene photodetectors integrated with silicon photonics, We also lay out the unavoidable performance trade-offs in meeting the requirements of various applications. In addition, we describe other opto-electronic devices based on this idea. Integrating two-dimensional materials with a silicon platform provides new opportunities in advanced integrated photonics.
基金Supported by the National Basic Research Program of China under Grant No 2012CB921900the National Natural Science Foundation of China under Grant Nos 61377035 and 11404264the Fundamental Research Funds for the Central Universities under Grant No 3102014JCQ01085
文摘We present a simple method to measure the topological charges of optical vortices with multiple singularities. Using a cylindrical lens, a vortex beam can decay into a light field distribution with multiple separated dark holes, whose number just equals the topological charge of the input beam. This conclusion is then verified via experiments and numerical simulations of the propagation of vortex beams with multiple singulaxities. This method is also reliable to measure the topological charges of broadband vortex beams with different distributions of singularities, which does not resort to multiple beam interferometrie experiments.
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2018YFA0307200 and 2017YFA0303800)the National Natural Science Foundations of China(Grant Nos.61522507 and 61775183)+1 种基金the Key Research and Development Program in Shaanxi Province of China(Grant No.2017KJXX-12)the Fundamental Research Funds for the Central Universities(Grant Nos.3102017jc01001 and 3102018jcc034)
文摘We demonstrate a reconfigurable black phosphorus electrical field transistor,which is van der Waals heterostructured with few-layer graphene and hexagonal boron nitride flakes.Varied homojunctions could be realized by controlling both source–drain and top-gate voltages.With the spatially resolved scanning photocurrent microscopy technique,photovoltaic photocurrents originated from the band-bending regions are observed,confirming nine different configurations for each set of fixed voltages.In addition,as a phototransistor,high responsivity(～800 mA/W)and fast response speed(～230μs)are obtained from the device.The reconfigurable van der Waals heterostructured transistors may offer a promising structure towards electrically tunable black phosphorus-based optoelectronic devices.
