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dielectric materials on a 2D material followed by postfabrication of PICs with lithography methods. [19][20][21][22] The layer transfer process of 2D materials on prefabricated PICs has the potential disadvantage of introducing strain and possible distortion of the 2D lattice if the strong van der Waals attraction between the 2D material and the dielectric surface produces conformal coverage over the sharp waveguide ridge corners, leading to reduced electron mobility, more phonon scattering centers, and possible degradation of device performance. While it is possible to planarize optical waveguides by additional processing involving deposition of low-refractive-index dielectrics followed by chemical-mechanical polishing, [6,8,13,23,24] such processes will reduce the optical overlap with the 2D material. For growing and patterning thin-film dielectric materials on 2D materials, the properties of both the thin-film dielectrics and 2D materials are usually affected adversely. [25][26][27][28] For example, the excellent properties of 2D materials can be destroyed by high-energy ions during the material growth process. Although some fabrication techniques for integrating 2D materials with dielectric materials like polymers [29] and chalcogenide glass [22] produce negligible effects on the material properties, they cannot universally be applied to many other types of dielectrics on 2D materials. In addition, few 2D materials can be grown on single-crystal materials with excellent optical properties. Therefore, a generic approach for integrating any types of 2D materials with any types of singlecrystal dielectrics is highly desired.The concept of "bound states in the continuum (BICs)" was first proposed by von Neumann and Wigner in 1929 with the mathematical construction of a 3D potential which can support perfectly confined states in a continuous band. [30] The radiation loss of these confined states can be eliminated by engineering their destructive interference with the continuous modes. [31][32][33][34][35][36][37][38][39] Harnessing BICs in PICs allows for low-loss light guidance and routing with a low-refractive-index waveguide on a high-refractive-index substrate. The light guided by the low-refractive-index waveguide can be confined to a region of the high-refractive-index substrate below the low-refractive-index waveguide. [40] Because the substrate is naturally flat, transferring a 2D material onto the high-refractive-index Integration of 2D materials on dielectric planar optical waveguides can make available new functionalities from the 2D materials' enhanced optoelectronic properties, such as nonlinearity, light emission, modulation, photodetection, and saturable absorption. However, the conventional integration schemes involving either the transfer of 2D materials onto prepatterned nonplanarized topology of photonic integrated circuits (PICs) or the growth and patterning of dielectric materials on 2D materials can degrade the properties of either the dielectric or the 2D material. Here, a fundamentally new ...

Many-core chip design has become a popular means to sustain the exponential growth of chip-level computing performance. The main advantage lies in the exploitation of parallelism, distributively and massively. Consequently, the on-chip communication fabric becomes the performance determinant. In the meantime, the introduction of Ultra-Wideband (UWB) interconnect brings in the new opportunity for giga-bps communication bandwidth, milliwatts communication power, and low cost implementation for millimeter range on-chip communication for future chip generations. In this paper, we study multi-channel wireless Network-on-Chip (McWiNoC) with ultra-short RF/wireless links for multi-hop communication. We first present the benefit of high bandwidth, low latency and flexible topology configurations provided by this new on-chip interconnection network. We then propose a distributed and deadlockfree location based routing scheme. We further design an efficient channel arbitration scheme to grant multi-channel access. With a few representative synthetic traffic patterns and SPLASH-II benchmarks, we demonstrate that McWiNoC can achieve 23.3% average performance improvement and 65.3% average end-to-end latency reduction over a baseline NoC of 8 × 8 metal wired mesh.

We report a software tool for post-correcting the linear and nonlinear image distortions of atomically resolved 3D spectrum imaging as well as 4D diffraction imaging. This tool improves the interpretability of distorted scanning transmission electron microscopy spectrum/diffraction imaging data.

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Loss reduction to improve the power efficiency in active integrated antenna (AIA) is a key design drive. This paper first analyzes the loss mechanism in a convention AIA structure. A new integration scheme of a GaN power amplifier (PA) transistor with an antenna without using any output matching network (OMN) and harmonic tuning network (HTN) is then proposed to construct a seamlessly integrated AIA. This is achieved by a novel design of a slot antenna with optimized input impedance at its fundamental frequency as well as for harmonic tuning, which essentially absorbs the OMN and HTN functions in the conventional Class-F power amplifier design. By eliminating these passive networks between the transistor and the antenna, the associated insertion and mismatch losses as well as the overall circuit size are reduced. For verification, two prototypes are designed, fabricated and measured, one with the integrated design and the other with a conventional design for comparison. Both AIAs operate between 3.4 and 3.6 GHz. Experimental results show that the power-added efficiency (PAE) of the seamlessly integrated AIA is over 52% within the operating band. Compared with the conventional cascaded design of a PA and an antenna, the PAE is improved by 14.2%. INDEX TERMS Amplifier integrated antenna, active antenna, Class-F power amplifier, loss reduction, seamless integration.

This paper investigates the design and analysis of a linear induction motor (LIM) drive for a prototype transportation system, which is levitated by the interaction force between high temperature superconducting (HTS) bulks placed on the ground and permanent magnets (PMs) mounted on the bottom of the vehicle, while the driving force is provided by a linear induction motor system on the side of the prototype vehicle. An equivalent electrical circuit is applied to predict the motor characteristics and the computation results show that the proposed LIM drive system is appropriate for driving the HTS maglev transportation prototype.