72 research outputs found
Design of a novel micro-laser formed by monolithic integration of a III-V pillar with a silicon photonic crystal cavity
A novel micro-laser configuration formed by integrating an InGaAs/InP pillar with a silicon photonic crystal cavity is proposed and analyzed in detail. Special attention is paid to designing the cavity such that it can accommodate large-size pillars without performance compromise. The Purcell effect is studied and predicted to be significant because of the close interaction between the cavity modes and the gain medium. An overall quality factor as high as 1 x 10(5) and a spontaneous emission factor close to unity are predicted. Possible limiting factors for laser performance, such as surface non-radiative recombination and the thermal dissipation properties are analyzed, and it is found that the proposed laser design is very robust. This comprehensive analysis suggests that the proposed micro-laser is a promising candidate for large-scale integration of micro-lasers on silicon for low power consumption applications, such as intra-chip optical communications
Room temperature InGaAs/InP distributed feedback laser directly grown on silicon
We report an optically pumped room-temperature O-band DFB laser, based on the buffer-less epitaxial growth of high quality InGaAs/InP waveguides directly on silicon wafer
Deformation and Failure Characteristics of the Rock Masses around Deep Underground Caverns
The deformation and failure characteristics of deep rock masses are the focus of this study on deep rock mass engineering. The study identifies the deformation and failure characteristics of a deep cavern under different ground stress conditions using model test and theoretical analysis methods. First, the similarity theory for model tests is introduced, and then the scale factors used in the present study are calculated according to the Froude criterion. Based on the study objectives, the details of the study methods (the similarity coefficient, the loading conditions, the test steps, etc.) are introduced. Finally, the failure characteristics of the deep cavern and the strain distribution characteristics surrounding the caverns under different ground stress conditions are identified using the model test. It was found that compared with shallow rock masses the rock masses of the deep cavern have a much greater tensile range, which reaches 1.5 times the diameter of the cavern under the conditions established in the present study. Under different ground stress conditions, there are differences in failure characteristics and the reasons of the differences were analyzed. The implication of the test results on the design of support system for deep caverns was presented
Room Temperature InP DFB Laser Array Directly Grown on (001) Silicon
Fully exploiting the silicon photonics platform requires a fundamentally new
approach to realize high-performance laser sources that can be integrated
directly using wafer-scale fabrication methods. Direct band gap III-V
semiconductors allow efficient light generation but the large mismatch in
lattice constant, thermal expansion and crystal polarity makes their epitaxial
growth directly on silicon extremely complex. Here, using a selective area
growth technique in confined regions, we surpass this fundamental limit and
demonstrate an optically pumped InP-based distributed feedback (DFB) laser
array grown on (001)-Silicon operating at room temperature and suitable for
wavelength-division-multiplexing applications. The novel epitaxial technology
suppresses threading dislocations and anti-phase boundaries to a less than 20nm
thick layer not affecting the device performance. Using an in-plane laser
cavity defined by standard top-down lithographic patterning together with a
high yield and high uniformity provides scalability and a straightforward path
towards cost-effective co-integration with photonic circuits and III-V FINFET
logic
DCP-Net: A Distributed Collaborative Perception Network for Remote Sensing Semantic Segmentation
Onboard intelligent processing is widely applied in emergency tasks in the
field of remote sensing. However, it is predominantly confined to an individual
platform with a limited observation range as well as susceptibility to
interference, resulting in limited accuracy. Considering the current state of
multi-platform collaborative observation, this article innovatively presents a
distributed collaborative perception network called DCP-Net. Firstly, the
proposed DCP-Net helps members to enhance perception performance by integrating
features from other platforms. Secondly, a self-mutual information match module
is proposed to identify collaboration opportunities and select suitable
partners, prioritizing critical collaborative features and reducing redundant
transmission cost. Thirdly, a related feature fusion module is designed to
address the misalignment between local and collaborative features, improving
the quality of fused features for the downstream task. We conduct extensive
experiments and visualization analyses using three semantic segmentation
datasets, including Potsdam, iSAID and DFC23. The results demonstrate that
DCP-Net outperforms the existing methods comprehensively, improving mIoU by
2.61%~16.89% at the highest collaboration efficiency, which promotes the
performance to a state-of-the-art level
III-V-on-silicon photonic integrated circuits for communication and sensing applications
We review the integration of III-V semiconductors on silicon photonic integrated circuits as a way of realizing fully integrated silicon photonic transceivers and short-wave infrared spectroscopic sensors
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