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We demonstrate an ultra-compact silicon polarization beam splitter with a coupling length of 0.768 μm. Lower than 2-dB insertion losses and over 10-dB extinction ratios are achieved over a wavelength range of 60 nm.

The characteristics Ge0.89Sn0.11 photodiodes were systematically investigated. A cutoff wavelength of 2.65 μm at 300 K and the peak detectivity of 4.3×109 Jones at 77 K were achieved. An infrared imaging of an object was demonstrated using the single Ge0.89Sn0.11 photodiode.

We presented optically pumped edge-emitting GeSn laser with 22.3% world-record maximum Sn content and 3 μm emission wavelength. Lasing threshold of 139 kW/cm2 at 77 K and maximum operating temperature of 150 K were achieved.

We experimentally demonstrate a two-bit thermal-optic ripple-carry full adder based on microdisk resonators in silicon photonics with the advantages of large bandwidth, low power consumption, and high scalability, paving the way to future optical computing.

The Ge 0.89 Sn 0.11 photoconductors with interdigitated electrodes have been investigated. High responsivity of 28.5 A/W and spectral response cutoff at 3.0 μm were achieved. The D∗ of 4.5 × 1010 cm·Hz1/2W−1 is close to that of extended-InGaAs detector.

A compact polarization splitter-rotator is experimentally demonstrated by using a subwavelength grating waveguide based directional coupler. Over 13 dB extinction ratios for both polarizations are achieved. Large tolerance (50 nm) to waveguide-width variation is also verified.

We present double heterostructure GeSn edge emitting laser. The structure was grown on a Si substrate using a commercial chemical vapor deposition with GeH 4 and SnCl 4 . The lasing threshold of 68 KW/cm2 at 10K and maximum laser operating temperature of 110 K was achieved.

We experimentally demonstrate an on-chip silicon 1×2 switch that routes 8 data channels on 4 modes and 2 polarizations. The insertion losses are < 8dB, and the crosstalk values are below −15dB. The 8 channels are tested with a 72-Gb/s signal.

A double heterostructure Ge/Ge0.9Sn0.1/Ge photodiode detector grown on Si was systematically characterized. Temperature-dependent device performance has been investigated. A cutoff wavelength of 2.6 μm and the peak responsivity of 0.19 A/W at 300 K were achieved.

We propose a compact (5μm×40μm) 2×2 electro-optic switch implemented by dual silicon photonic crystal nanobeam (PCN) cavities. A switching power of 2.6 fJ/bit is numerically demonstrated. Extinction ratios of 14.2/13.4 dB are achieved at through/drop ports.

A Ge 0.95 Sn 0.05 /Ge 0.9 Sn 0.1 /Ge 0.95 Sn 0.05 single quantum well was grown on Si via chemical vapor deposition. Temperature-dependent Photoluminescence shows the emission peak from the GeSn well. The studied structure aims for group-IV based efficient light source on Si.

The Ge 0.9 Sn 0.1 photoconductor was fabricated with interdigitated structures on Si using a CMOS-compatible process. Temperature-dependent responsivity and specific detectivity were measured. The peak responsivity of 2.85A/W at 77K was achieved due to enhanced photoconductive gain.

At wavelengths of 1.55 to 3.0 μm, theoretical simulations were made of electro-optical 2 x 2 switching utilizing a thin-film of Ge2Sb2Te5 or GeTe or GeSe that offers two voltage-triggered self-holding optical states. Low loss and low crosstalk were predicted but experiments are needed to confirm the theory.

Group IV and III–V semiconductor photonic devices are prime candidates for photonic and opto-electronic (OEIC) applications in the 1.8 to 5.0 µm infrared wavelength range. Si-based active photonics in the GeSn/SiGeSn heterosystem (LDs, PDs, LEDs, amplifiers, EOMs) offers the Si CMOS “foundry advantage” for high-volume low-cost OEIC manufacture. Two MIR applications stand out: (1) deployment of GeSn SOI-based OEICs in a new “supplemental” global fiber-optic network at ∼ 2 um wavelengths; (2) creation/deployment of GeSn-related photonic chem-bio-physical sensor OEICs (as well as night-vision-imaging chips) in hand-held tablets and smart phones. The new smart sensors will be part of a local or global network-of-sensors utilizing the “internet of things.”

Here we demonstrate a reconfigurable electro-optical directed-logic circuit based on a 4-fold array of switches. We showed that this circuit can be reconfigured to perform arbitrary two-input logic functions with speed up to 3 Gb/s.

Thin film Ge1-xSnx photodetectors fabricated on Si using a CMOS compatible process had responsivities at 1.55 mm of 6.59, 1.49, 2.63, and 0.84 mA/W for 0.9, 2.57, 3.2, and 7.0 % Sn. Spectral response for a Ge0.93Sn0.07 photodetector had extended infrared response out to 2.2 mm.

We report on strong index modulation of ITO-hybrid-plasmon gate stacks at telecomm wavelengths verified by gated ellipsometry for the first time. Using these results we design a compact 3-waveguide electro-optic switch for photonic integration.

A lateral p-n junction nanobeam electro-optic modulator for the 8 micron regime is presented. Owing to a strong free-carrier absorption effect, an ultralow switching energy is achieved, while utilizing a small footprint, monolithic, and VLSI-compatible implementation.

Photoluminescence (PL) from Ge1-xSnx grown on Si by CVD was investigated for Sn composition of 0.9, 3.2, 6, and 7%, respectively. The direct and indirect band transitions were analyzed at different temperatures.

We design low-loss single-mode GeSn mid-infrared waveguides on group-IV substrates including Si substrates and Ge-on-SOI substrates. The waveguide geometries under single mode condition are optimized for different GeSn alloy compositions and polarizations.

Spectral evolution of a photonic crystal waveguide under electro-optic tuning revealed interband scattering signature from the TM-like mode to the odd TE-like mode in active devices. The impact on novel optical isolators is discussed.

By multiplexing different sized structures within the unit cell of the gap-mode plasmon resonance structure, perfect light absorption has been achieved with broader near-perfect absorption of light.

Metal nanoridges can support well-confined propagating surface plasmon modes. Various geometries of silver nanoridges are investigated in this work. It is found that semicircular top nanoridges are optimal for supporting high figure-of-merit surface plasmon modes.

We show a scalable and reconfigurable optical logic architecture based on a regular array of integrated optical switches. We present a proof-of-principle demonstration with a 2 ×2 switch array that can perform arbitrary two-input logic functions.

Perfect light absorptions can be achieved with metal-dielectric-metal structures. In this talk, we will discuss how multiplexed metal nanostructures can control the metamaterial absorption light spectral bands.

t has been found that the nano-ridge plasmon modes are quasi-TEM modes. The quasi-TEM mode profiles reveal that the propagation of free electron oscillation on the top of the metal nano-ridges contributes to the tightly confined plasmon ridge mode.

Silicides, heavily-doped semiconductors, and semimetals are investigated theoretically and experimentally as surface plasmon hosts for infrared surface plasmon resonance biosensors. Tighter IR mode confinement than for usual Au gives better overlap with biological analytes.

Silicon-based plasmonic waveguides are proposed and studied theoretically. A silicon core, silicide underlay, and metal overlay yield propagation losses estimated to be less than 15 cm-1over the 50 ?m to 1000 ?m wavelength range.

This paper will survey recent developments in Silicon-based light emitters, waveguide structures, ultrafast modulators, routers, direct-bandgap GeSn/Ge/SiGeSn/Si structures, photonic-crystal devices and subwavelength-plasmonic devices. Components can be designed for a wavelength within 0.3 to 100 μm.