In order to realize the ultrastrong absorption of graphene with electrical modulation properties, we designed a composite structure of graphene and parity-time(PT) symmetry photonic crystal, which is achieved by placi...In order to realize the ultrastrong absorption of graphene with electrical modulation properties, we designed a composite structure of graphene and parity-time(PT) symmetry photonic crystal, which is achieved by placing the graphene layer on the top layer of the PT symmetry photonic crystal. In this paper, the absorption properties of graphene and the electrical modulating properties of the structure were theoretically analyzed based on the transfer matrix method. The result shows that the proposed structure can achieve the absorption of 31.5 d B for the communication wavelength of 1550 nm;meanwhile,by setting the electric field intensity to ±0.02 V/nm, the absorption of graphene can be largely modulated to realize an electrically switchable effect, the modulation depth of graphene absorption can reach nearly 100%, and the operation speed is also close to 8.171 GHz. This investigation provides a novel approach to design graphene-based optoelectronic devices and optical communication devices.展开更多
Reducing the overall vehicle weight is an efficient,system-level approach to increase the drive range of electric vehicle,for which structural parts in auto-frame may be replaced by battery modules.Such battery module...Reducing the overall vehicle weight is an efficient,system-level approach to increase the drive range of electric vehicle,for which structural parts in auto-frame may be replaced by battery modules.Such battery modules must be structurally functional,e.g.,energy absorbing,while the battery cells are not necessarily loading–carrying.We designed and tested a butterfly-shaped battery module of prismatic cells,which could self-unfold when subjected to a compressive loading.Angle guides and frictionless joints were employed to facilitate the large deformation.Desired resistance to external loading was offered by additional energy absorption elements.The battery-module behavior and the battery-cell performance were controlled separately.Numerical simulation verified the experimental results.展开更多
A selected area growth wavelength converter based on a PD-EAM optical logic gate for WDM application is presented, integrating an EML transmitter and a SOA-PD receiver. The design, fabrication, and DC characters were ...A selected area growth wavelength converter based on a PD-EAM optical logic gate for WDM application is presented, integrating an EML transmitter and a SOA-PD receiver. The design, fabrication, and DC characters were analyzed. A 2 Gb/s NRZ signal based on the C-band wavelength converted to 1555 nm with the highest extinction ratio of 7 dB was achieved and wavelength converted eye diagrams with eyes opened were presented.展开更多
基金This work was supported by the National Natural Science Foundation of China(Nos.61307050 and 61701271)the Natural Science Foundation of Shandong Province(No.ZR2016AM27)。
文摘In order to realize the ultrastrong absorption of graphene with electrical modulation properties, we designed a composite structure of graphene and parity-time(PT) symmetry photonic crystal, which is achieved by placing the graphene layer on the top layer of the PT symmetry photonic crystal. In this paper, the absorption properties of graphene and the electrical modulating properties of the structure were theoretically analyzed based on the transfer matrix method. The result shows that the proposed structure can achieve the absorption of 31.5 d B for the communication wavelength of 1550 nm;meanwhile,by setting the electric field intensity to ±0.02 V/nm, the absorption of graphene can be largely modulated to realize an electrically switchable effect, the modulation depth of graphene absorption can reach nearly 100%, and the operation speed is also close to 8.171 GHz. This investigation provides a novel approach to design graphene-based optoelectronic devices and optical communication devices.
基金supported by the Advanced Research Projects Agency-Energy(ARPA-E) under Grant No.DEAR0000396
文摘Reducing the overall vehicle weight is an efficient,system-level approach to increase the drive range of electric vehicle,for which structural parts in auto-frame may be replaced by battery modules.Such battery modules must be structurally functional,e.g.,energy absorbing,while the battery cells are not necessarily loading–carrying.We designed and tested a butterfly-shaped battery module of prismatic cells,which could self-unfold when subjected to a compressive loading.Angle guides and frictionless joints were employed to facilitate the large deformation.Desired resistance to external loading was offered by additional energy absorption elements.The battery-module behavior and the battery-cell performance were controlled separately.Numerical simulation verified the experimental results.
基金Project supported by the Nationa lHigh Technology Research and Development Program of China(Nos.2011AA010303,2012AA012203)the State Key Program for Basic Research of China(No.2011CB301702)the National Natural Science Foundation of China(Nos.61021003,61090392)
文摘A selected area growth wavelength converter based on a PD-EAM optical logic gate for WDM application is presented, integrating an EML transmitter and a SOA-PD receiver. The design, fabrication, and DC characters were analyzed. A 2 Gb/s NRZ signal based on the C-band wavelength converted to 1555 nm with the highest extinction ratio of 7 dB was achieved and wavelength converted eye diagrams with eyes opened were presented.
