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We demonstrate a dual-polarization, single-wavelength transceiver with BER below soft-decision FEC (

Ineffective site-specific delivery has seriously impeded the efficacy of nanoparticle-based drugs to a disease site. Here, we report the preparation of three different shapes (sphere, scroll, and oblate) to systematically evaluate the impact of the marginative delivery on the efficacy of magnetic resonance (MR) imaging-guided X-ray irradiation at a low dose of 1 Gy. In addition to the shape effect, the therapeutic efficacy is investigated for the first time to be strongly related to the structure effect that is associated with the chemical activity. The enhanced particle-vessel wall interaction of both the flat scroll and oblate following margination dynamics leads to greater accumulation in the lungs, resulting in superior performance over the sphere against lung tumor growth and suppression of lung metastasis. Furthermore, the impact of the structural discrepancy in nanoparticles on therapeutic efficacy is considered. The tetragonal oblate reveals that the feasibility of the charge-transfer process outperforms the orthorhombic scroll and cubic sphere to suppress tumors. Finally, surface area is also a crucial factor affecting the efficacy of X-ray treatments from the as-prepared particles.

Reservoir computing has emerged as a lightweight, high-speed machine learning paradigm. We introduce a new optoelectronic reservoir computer for image recognition, in which input data is first pre-processed offline using two convolutional neural network layers with randomly initialized weights, generating a series of random feature maps. These random feature maps are then multiplied by a random mask matrix to generate input nodes, which are then passed to the reservoir computer. Using the MNIST dataset in simulation, we achieve performance in line with state-of-the-art convolutional neural networks (1% error), while potentially offering order-of-magnitude improvement in training speeds.

We demonstrate a silicon micro-ring modulator supporting 128 Gb/s NRZ modulation with SNR=5.2, ER=3.8dB, 0.8 Vpp drive swing, and 5.3 fJ/bit power consumption. We have also achieved 192 Gb/s PAM-4 modulation with TDECQ of 2.5dB.

We demonstrate an all-silicon micro-ring resonant photodetector with a responsivity of 0.23 A/W and dark current

InGaN/GaN self-organized quantum dots and similar dots in GaN nanowires are formed by strain relaxation and the luminescence from these nanostructures extends to longer wavelengths than generally obtained with quantum wells. We have exploited this advantage by incorporating these nanostructures in the gain region of edge-emitting diode lasers. Here, we describe the characteristics of 650 nm self-organized quantum dot lasers epitaxially grown on GaN and 1.3 μ m dot-in-nanowire array lasers grown on (001) Si by molecular beam epitaxy. The devices are characterized by relatively low threshold currents, excellent temperature stability ( T 0 > 200 K), and differential gain ∼10–16 cm2. The highest measured small-signal modulation bandwidth of the dot-in-nanowire laser is 3.3 GHz. The experiments have been complemented by theoretical modeling of the self-organized quantum dots and lasers made with them. These new classes of devices open up new opportunities in applications such as displays, optical data storage, heads-up displays in automobiles, plastic fiber communication, and silicon photonics.

A monolithic interferometric tunable laser with a tuning range of 44 nm and linewidth below 700 kHz across all channels is reported. The laser features an intra-cavity coupler consisting of three electro-optically tunable arms with distinct lengths for supermode selection.

A novel method to achieve single-fundamental-mode lasing and higher order mode suppression using a multi-layer, patterned, dielectric anti-phase filter is employed on the top of oxide-confined vertical-cavity surface-emitting lasers (VCSELs). Dielectric layers are deposited and patterned on individual VCSELs in a wafer-scale process to modify (increase/decrease) the mirror reflectivity across the oxide aperture via anti-phase reflections, creating spatially dependent threshold material gain and VCSEL lasing-mode control. A 1-D plane-wave propagation method is used to calculate the dielectric layer thicknesses in each spatial region needed to facilitate or suppress lasing. A single-fundamental-mode, continuous-wave output power of 3.5 mW is achieved at a lasing wavelength of 850 nm. This additive, non-destructive method allows for mode selection at any lasing wavelength and for any VCSEL layer structure without the need for destructive etching techniques or epitaxial regrowth. It also offers the capability of a tailored filter design based on available materials and deposition methods.

Using the Vernier effect and the interference between its three branches, the proposed self-imaging multi-mode-interferometer (MMI)-based tunable laser can access all ITU channels across C-band with high side-mode suppression ratios (SMSR).

The light-emitting transistor (LET) is examined as a fundamental circuit element for electronic-photonic integration. Basic device properties, methods of integration, and simple electronic-photonic circuits built upon the LET are examined. Novel materials, methods, and devices for heterogeneous integration are also presented.

We present a physical model for recently demonstrated high indium content self-assembled In0.4Ga0.6N/GaN quantum dot (QD)-based ridge-waveguide lasers emitting at red wavelengths. The strain distribution in the QD is calculated using linear elastic theory with the application of shrink-fit boundary condition at the InGaN/GaN material interface, and the electronic states are evaluated using a single-band effective mass Hamiltonian. A Schrodinger-Poisson self-consistent solver is used to describe the effect of charge screening under current injection. Our theoretical result shows a good match to the measured Hakki-Paoli gain spectrum. Combining the calculated gain spectrum and cavity properties, we have developed a device-level simulation to successfully explain the electrical and optical characteristics of this specific laser. Possible solutions to improving the device performance have been explored.

The integration of III-V or III-N materials onto selected regions of a silicon or silicon-on-insulator (SOI) with the goal of creating electronic-photonic circuits is examined. Epitaxial transfer and bonding methods are discussed, as well as issues of CMOS compatibility and the thermal environment of the III-V devices. Possible devices for future electronic-photonic integration are also discussed.

Integration of compound semiconductors with CMOS provides a path for improving performance and increasing functionality. Methods for integrating photonic materials are examined, and the resulting thermal environment modeled. Integration of III-N materials is also discussed.

We present a comprehensive study for a new three-branch widely tunable semiconductor laser based on a self-imaging, lossless multi-mode interference (MMI) coupler. We have developed a general theoretical framework that is applicable to all types of interferometric lasers. Our analysis showed that the three-branch laser offers high side-mode suppression ratios (SMSRs) while maintaining a wide tuning range and a low threshold modal gain of the lasing mode. We also present the design rules for tuning over the dense-wavelength division multiplexing grid over the C-band.

We present low-threshold dielectric-cavity surface-emitting microlasers working at room temperature under continuous-wave electrical injection with device diameter down to 2 mm. Size-dependent lasing properties are predicted theoretically and demonstrated experimentally.

A comprehensive theoretical model for the high contrast grating tunable VCSELs is presented. The tunability of the resonance and the L-I curves are investigated. Our theoretical results agree very well with the experimental data.

We present a comprehensive model for In(0.18)Ga(0.82)N/GaN self-assembled quantum dot (QD) active material. The strain distribution in the QD structure is studied using linear elastic theory with the application of the shrink-fit boundary condition at the material interface. Subsequent calculations also predict the strain-induced quantum-confined Stark effect (QCSE). Under carrier injection, the overall effect of band bending and charge screening is studied by solving the Schrödinger and Poisson equations self-consistently. The optical gain spectrum of the InGaN/GaN QD active material is calculated based on the electronic states solved from the Schrödinger-Poisson equation, and both the calculated material gain peak and emission wavelength agree well with the measured experimental data.