Micromanipulation of InP lasers with optoelectronic tweezers for integration on a photonic platform

The integration of light sources on a photonic platform is a key aspect of the fabrication of self-contained photonic circuits with a small footprint that does not have a definitive solution yet. Several approaches are being actively researched for this purpose. In this work we propose optoelectronic tweezers for the manipulation and integration of light sources on a photonic platform and report the positional and angular accuracy of the micromanipulation of standard Fabry-Pérot InP semiconductor laser die. These lasers are over three orders of magnitude bigger in volume than any previously assembled with optofluidic techniques and the fact that they are industry standard lasers makes them significantly more useful than previously assembled microdisk lasers. We measure the accuracy to be 2.5 ± 1.4 µm and 1.4 ± 0.4° and conclude that optoelectronic tweezers are a promising technique for the micromanipulation and integration of optoelectronic components in general and semiconductor lasers in particular

A 30 Gb/s CMOS driver integrated with silicon photonics MZM

A voltage mode modulator driver is proposed in the TSMC 65nm low power CMOS process. In the electrical testing, the driver itself can achieve a bit rate of 40Gb/s with the single-ended output swing of 1.65V. Unlike equivalent CML modulator drivers, when the proposed driver is integrated with the silicon photonic MZM, it does not require an additional biasing network. The integrated electro-optic transmitter can achieve 30Gb/s with an extinction ratio of 4.05dB, with the power consumption of main driver being 323mW

Recent breakthroughs in carrier depletion based silicon optical modulators

The majority of the most successful optical modulators in silicon demonstrated in recent years operate via the plasma dispersion effect and are more specifically based upon free carrier depletion in a silicon rib waveguide. In this work we overview the different types of free carrier depletion type optical modulators in silicon. A summary of some recent example devices for each configuration is then presented together with the performance that they have achieved. Finally an insight into some current research trends involving silicon based optical modulators is provided including integration, operation in the mid-infrared wavelength range and application in short and long haul data transmission link

Localised tuneable composition single crystal silicon-germanium-on-insulator for low cost devices

The realisation of high quality silicon-germanium-on-insulator (SGOI) is a major goal for the field of silicon photonics because it has the potential to enable extremely low power active devices functioning at the communication wavelengths of 1.3 µm and 1.55 µm. In addition, SGOI has the potential to form faster electronic devices such as BiCMOS transistors, and could also form the backbone of a new silicon photonics platform that extends into the mid-IR wavelengths for applications in, amongst others, sensing and telecoms. In this paper, we present a novel method of forming single crystal, defect free SGOI using a rapid melt growth technique. We use tailored structures to form localised uniform composition SGOI strips, which are suitable for state of the art device fabrication. This technique could pave the way for the seamless integration of electronic and photonic devices using only a single, low cost Ge deposition step

A Low Cost Technique for Adding Microlasers to a Silicon Photonic Platform

In this paper we report the physical micromanipulation of standard InP telecommunications laser die in a liquid medium by means of optoelectronic tweezers. Optoelectronic tweezers have been shown to use much less optical power than optical tweezers, they do not require a coherent light source to function and the creation of multiple traps is straightforward. These properties make the technique a very good candidate for the massive parallel micromanipulation of optoelectronic components for assembly on a photonic platform. We discuss the positional and orientation accuracy of the optoelectronic tweezers in relation to the alignment requirements for low-loss coupling between the light sources and the other components in a photonic platform. Our experiments indicate that the accuracy is better than 2 µm and 2◦ for translations and rotations, respectively

Low-loss slot waveguides with silicon (111) surfaces realized using anisotropic wet etching

We demonstrate low-loss slot waveguides on silicon-on-insulator (SOI) platform. Waveguides oriented along the (11-2) direction on the Si (110) plane were first fabricated by a standard e-beam lithography and dry etching process. A TMAH based anisotropic wet etching technique was then used to remove any residual side wall roughness. Using this fabrication technique propagation loss as low as 3.7dB/cm was realized in silicon slot waveguide for wavelengths near 1550nm. We also realized low propagation loss of 1dB/cm for silicon strip waveguides

Cataclysmic Variables in the First Year of the Zwicky Transient Facility

Using selection criteria based on amplitude, time, and color, we have identified 329 objects as known or candidate cataclysmic variables (CVs) during the first year of testing and operation of the Zwicky Transient Facility. Of these, 90 are previously confirmed CVs, 218 are strong candidates based on the shape and color of their light curves obtained during 3–562 days of observation, and the remaining 21 are possible CVs but with too few data points to be listed as good candidates. Almost half of the strong candidates are within 10 deg of the galactic plane, in contrast to most other large surveys that have avoided crowded fields. The available Gaia parallaxes are consistent with sampling the low mass transfer CVs, as predicted by population models. Our follow-up spectra have confirmed Balmer/helium emission lines in 27 objects, with four showing high-excitation He ii emission, including candidates for an AM CVn, a polar, and an intermediate polar. Our results demonstrate that a complete survey of the Galactic plane is needed to accomplish an accurate determination of the number of CVs existing in the Milky Way