InP-based membrane photodetectors for optical interconnects to Si

We present the design, fabrication and a characterization of an InP-based membrane photodetector on an SOI wafer containing a Si-wiring photonic circuit. Waveguide losses in the Si-wiring circuit are below 5 dB/cm. Measured detector responsivity is 0.45 A/W. The photonic device fabrication is compatible with wafer scale processing steps, guaranteeing compatibility towards future generation electronic IC processing

Two-dimensional optical beam steering with InP-based photonic integrated circuits

Two-dimensional optical beam steering using an InP photonic integrated circuit has been demonstrated. Lateral beam steering controlled by a 1-D phased array has been made easier through on-chip interferometer monitors. Longitudinal beam steering controlled by the input wavelength has demonstrated an efficiency of 0.14 degrees/nm. Very fast beam steering (>10(7) degrees/s) in both dimensions has been demonstrated as well. As the latest development, a widely tunable sampled-grating distributed Bragg reflector laser has been monolithically integrated and 2-D beam steering has been demonstrated with this on-chip tunable laser source

InP/InGaAs photodetector on SOI circuitry

We present the design, fabrication and characterization of an InP-based membrane photodetector on an SOI wafer containing a Si-wiring photonic circuit. Measured detector responsivity and 3 dB bandwidth are 0.45 A/W and 33 GHz, respectively. The photonic device fabrication is compatible with wafer scale processing steps, guaranteeing compatibility towards future generation electronic IC processing

A photonic interconnect layer on CMOS

We propose and demonstrate a photonic interconnect layer consisting of heterogeneous microdisk lasers and microdetectors integrated with a nanophotonic silicon waveguide circuit. The photonic layer is fabricated using waferscale processes and a die-to-wafer molecular bonding process

Observation of Gravitational Waves from the Coalescence of a 2.5−4.5 M⊙2.5-4.5~M_\odot Compact Object and a Neutron Star

International audienceWe report the observation of a coalescing compact binary with component masses $2.5-4.5~M_\odot$ and $1.2-2.0~M_\odot$ (all measurements quoted at the 90% credible level). The gravitational-wave signal GW230529_181500 was observed during the fourth observing run of the LIGO-Virgo-KAGRA detector network on 2023 May 29 by the LIGO Livingston Observatory. The primary component of the source has a mass less than $5~M_\odot$ at 99% credibility. We cannot definitively determine from gravitational-wave data alone whether either component of the source is a neutron star or a black hole. However, given existing estimates of the maximum neutron star mass, we find the most probable interpretation of the source to be the coalescence of a neutron star with a black hole that has a mass between the most massive neutron stars and the least massive black holes observed in the Galaxy. We estimate a merger rate density of $55^{+127}_{-47}~\text{Gpc}^{-3}\,\text{yr}^{-1}$ for compact binary coalescences with properties similar to the source of GW230529_181500; assuming that the source is a neutron star-black hole merger, GW230529_181500-like sources constitute about 60% of the total merger rate inferred for neutron star-black hole coalescences. The discovery of this system implies an increase in the expected rate of neutron star-black hole mergers with electromagnetic counterparts and provides further evidence for compact objects existing within the purported lower mass gap