By designing and fabricating a series of dual-interferometer coupled silicon microrings, the coupling condition of the pump, signal, and idler beams can be engineered independently and then we carried out both the con...
详细信息
By designing and fabricating a series of dual-interferometer coupled silicon microrings, the coupling condition of the pump, signal, and idler beams can be engineered independently and then we carried out both the continuous-wave and pulse pumped four-wave mixing experiments to verify the dependence of conversion efficiency on the coupling conditions of the four interacting beams, respectively. Under the continuous-wave pump, the four-wave mixing efficiency gets maximized when both the pump and signal/idler beams are closely operated at the critical coupling point, while for the pulse pump case, the efficiency can be enhanced greatly when the pump and converted idler beams are all overcoupled. These experiment results agree well with our theoretical calculations. Our design provides a platform for explicitly characterizing the four-wave mixing under different pumping conditions, and offers a method to optimize the four-wave mixing, which will facilitate the development of on-chip all-optical signal processing with a higher efficiency or reduced pump power.
One of the most challenging problems that limit the practical application of carbon-based photothermal nanofluids is their poor dispersion stability and tendency to form aggregation. Herein, by using Fe3O4@graphene hy...
详细信息
One of the most challenging problems that limit the practical application of carbon-based photothermal nanofluids is their poor dispersion stability and tendency to form aggregation. Herein, by using Fe3O4@graphene hybrid nanoparticles as a model system, we proposed a new method to prepare stably dispersed silicone oilbased solar-thermal nanofluids that can operate at high temperatures than water-based fluids. The introduction of Fe3O4nanoparticles between graphene nanosheets not only physically increases the inter-plane distance of the graphene nanosheet but also provides numerous anchoring points for surface modification. Phosphate-terminated polydimethylsiloxane chains, which have high compatibility with the silicone oil base fluids and hightemperature stability, were synthesized and utilized to modify the Fe3O4nanoparticle surfaces. The attached chains create steric hindrance and effectively screen the strong inter-plane van der Waals attraction between graphene sheets. Dispersion stability of the nanofluids with different concentrations of surface-modified hybrid nanoparticles and heated under different temperatures was investigated. We have demonstrated that such fluids could maintain stable dispersion under a heating temperature up to 150 °C depending on the concentration of the hybrid nanoparticles. The resultant nanofluids maintained stable dispersion after repeated heating and were employed for consistent direct solar-thermal energy harvesting at 100 °C.
In this Letter,we reported the preliminary results of an integrating periodically capacitive-loaded traveling wave electrode(CL-TWE)Mach–Zehnder modulator(MZM)based on InP-based multiple quantum well(MQW)optical *** ...
详细信息
In this Letter,we reported the preliminary results of an integrating periodically capacitive-loaded traveling wave electrode(CL-TWE)Mach–Zehnder modulator(MZM)based on InP-based multiple quantum well(MQW)optical *** device configuration mainly includes an optical Mach–Zehnder interferometer,a direct current electrode,two phase electrodes,and a CL-TWE consisting of a U electrode and an I *** modulator was fabricated on a 3 *** epitaxial wafer by standard photolithography,inductively coupled plasma dry etching,wet etching,electroplating,*** results show that the MZM exhibits a3 dB electro-optic bandwidth of about 31 GHz,a Vπof 3 V,and an extinction ratio of about 20 dB.
A low temperature fine pitch wafer scale bonding process through Au-In solid liquid inter diffusion bonding is discussed in this paper. 20 μm fine pitch gold and indium miro-bumps with 10 μm diameter are fabricated ...
详细信息
ISBN:
(数字)9781728168265
ISBN:
(纸本)9781728168272
A low temperature fine pitch wafer scale bonding process through Au-In solid liquid inter diffusion bonding is discussed in this paper. 20 μm fine pitch gold and indium miro-bumps with 10 μm diameter are fabricated on two oxidized silicon wafers. Then the wafer bonding process is accomplished at 180 °C with less than 2 μm alignment accuracy. Daisy chains of nearly 2500 interconnects with a fixed contact size of 10×10 μm 2 connected successfully. Besides, there is no significant change of the daisy chain resistance after temperature cycling test. An average die shear strength of more than 20 MPa is also achieved. This work shows great potential of Au-In solid liquid inter diffusion bonding for future high density wafer level packaging and heterogeneous integration.
We investigate the influence of fin architecture on linearity characteristics of AlGaN/*** is found that the Fin FET with scaled fin dimensions exhibits much flatter Gm characteristics than the one with long fins as w...
详细信息
We investigate the influence of fin architecture on linearity characteristics of AlGaN/*** is found that the Fin FET with scaled fin dimensions exhibits much flatter Gm characteristics than the one with long fins as well as planar *** to the comparative study,we provide direct proof that source resistance rather than tri-gate structure itself dominates the Gm ***,power measurements show that the optimized FinFET is capable of delivering a much higher output power density along with significant improvement in linearity characteristics than conventional planar *** study also highlights the importance of fin design in GaN-based FinFET for microwave power application,especially high-linearity applications.
The spin-polarized photocurrent is used to study the in-plane electric field dependent spin transport in undoped InGaAs/AlGaAs multiple quantum wells. In the temperature range of 77–297 K, the spin-polarized photocur...
详细信息
The spin-polarized photocurrent is used to study the in-plane electric field dependent spin transport in undoped InGaAs/AlGaAs multiple quantum wells. In the temperature range of 77–297 K, the spin-polarized photocurrent shows an anisotropic spin transport under different oriented in-plane electric fields. We ascribe this characteristic to two dominant mechanisms: the hot phonon effect and the Rashba spin-orbit effect which is influenced by the in-plane electric fields with different orientations. The formulas are proposed to fit our experiments, suggesting a guide of potential applications and devices.
We report excellent dc and RF performance of high-linearity AIGaN/GaN FinFETs with 100 nm T-gate. Besides a high fT of 65 GHz enabled by scaled gate length, good linearity characteristics of Gm and fT/fmax are demonst...
详细信息
Notice of Violation of IEEE Publication Principles "A 220GHz GaN HEMT Power Amplifier" by Yan Sun, Shaobing Wu, Haiyan Lu, Yuechan Kong, Tangsheng Chen, Zhonghui Li, Qingsheng Zeng in the Proceedings of the ...
ISBN:
(数字)9781728153049
ISBN:
(纸本)9781728153056
Notice of Violation of IEEE Publication Principles "A 220GHz GaN HEMT Power Amplifier" by Yan Sun, Shaobing Wu, Haiyan Lu, Yuechan Kong, Tangsheng Chen, Zhonghui Li, Qingsheng Zeng in the Proceedings of the Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall), December 2019, pp. 2978-2981 After careful and considered review of the content and authorship of this paper by a duly constituted expert committee, this paper has been found to be in violation of IEEE's Publication Principles. This paper copied content from the papers cited below. The original content was copied without attribution (including appropriate references to the original authors and/or paper titles) and without permission. "A Beyond 110 GHz GaN Cascode Low-Noise Amplifier with 20.3 dBm Output Power" by Rainer Weber, Maciej Cwiklinski, Sandrine Wagner, Roger Lozar, Hermann Massler, Peter Bruckner, Rudiger Quay in the Proceedings of the IEEE/MTT-S International Microwave Symposium (IMS), June 2018, pp. 1499-1502 "190-GHz G-Band GaN Amplifier MMICs with 40GHz of Bandwidth" by Maciej Cwiklinski, Peter Bruckner, Stefano Leone, Christian Friesicke, Roger Lozar, Hermann Massler, Rudiger Quay, and Oliver Ambacher in the Proceedings of the IEEE/MTT-S International Microwave Symposium (IMS), June 2019, pp. 1257???1260 In this paper, we present the first millimeter-wave GaN HEMT monolithicintegrated circuit (MMIC) amplifier with an operating frequency at 220 GHz. This MMIC has a small-signal gain well above 11 dB at 222 GHz. Moreover, the use of gallium nitride technology allows for achieving state-of-the-art saturated output power, up to 14dBm at 222 GHz. To our knowledge, the measured gain and output power levels are the best among any of the GaN MMICs beyond 200 GHz reported to date.
This paper investigated the DC and RF performance of the In P double heterojunction bipolar transistors（DHBTs）transferred to RF CMOS wafer *** measurement results show that the maximum values of the DC current gain ...
详细信息
This paper investigated the DC and RF performance of the In P double heterojunction bipolar transistors（DHBTs）transferred to RF CMOS wafer *** measurement results show that the maximum values of the DC current gain of a substrate transferred device had one emitter finger,of 0.8μm in width and 5μm in length,are changed unobviously,while the cut-off frequency and the maximum oscillation frequency are decreased from 220to 171 GHz and from 204 to 154 GHz,*** order to have a detailed insight on the degradation of the RF performance,small-signal models for the In P DHBT before and after substrate transferred are presented and comparably *** extracted results show that the degradation of the RF performance of the device transferred to RF CMOS wafer substrate are mainly caused by the additional introduced substrate parasitics and the increase of the capacitive parasitics induced by the substrate transfer process itself.
暂无评论