Bias effects on the electro-optic response of Ge-on-Si waveguide photodetectors

Silicon photonics, allowing for the integration of optoelectronic components into CMOS-compatible platforms, has shown great promise in the development of next-generation telecommunication systems and fast, low-power data interconnects. Within this framework, the increasing transistor integration and power dissipation density has led, during the last decades, to a steady decrease of the CMOS bias voltages. This trend may also affect the operation of silicon photonics components: the present work is focused on the effects of lower bias in Ge-on-Si waveguide photodetectors (WPDs), using the electro-optic (EO) frequency response as a figure of merit

Modeling the electronic transport in FinFET-like lateral Ge-on-Si pin waveguide photodetectors for ultra-wide bandwidth applications

We determined the velocities of photogenerated electrons and holes in FinFET-like lateral Ge-on-Si waveguide photodetectors with Monte Carlo transport simulation. The calculated carrier velocities were used in a 3D multiphysics model focused on the investigation of the electro-optic frequency response. The good match between the bandwidths predicted by the model and the corresponding experimental values available from the literature, larger than 200 GHz, indicates the importance of moving beyond conventional drift-diffusion models for a realistic description of next-generation high-speed integrated photodetectors

3D multiphysics transient modeling of vertical Ge-on-Si pin waveguide photodetectors

We report transient simulations of Ge-on-Si vertical pin waveguide photodetectors (WPDs), where the optical generation term used by the time-domain model is the FDTD solution of the electromagnetic problem treated as a spatially-distributed pulsed signal. This approach, validated against experimental measurements of the frequency response, paves the way to future studies of the dynamic response of WPDs, enabling the description of complex modulation schemes including saturation effects and current tails due to slow carriers

Next-generation long-wavelength infrared detector arrays: competing technologies and modeling challenges

In this paper, Sb-based superlattice fabrication processing is based on standard III-V technology, implying lower costs of mass production and constituting a relatively new alternative for an IR material system in LWIR and VLWIR bands

Modeling the frequency response of vertical and lateral Ge-on-Si waveguide photodetectors: Is 3D simulation unavoidable?

Using a 3D multiphysics model as a reference, we investigate the achievements and limitations of a simpler 2D drift-diffusion model to reproduce and optimize the electrooptical frequency response of vertical and lateral Ge-on-Si waveguide photodetectors

Five-year outcomes of chronic total occlusion treatment with a biolimus A9-eluting biodegradable polymer stent versus a sirolimus-eluting permanent polymer stent in the LEADERS all-comers trial

Background: Few data are available on long-term follow-up of drug-eluting stents in the treatment of chronic total occlusion (CTO). The LEADERS CTO sub-study compared the long-term results in CTO and non-CTO lesions of a Biolimus A9™-eluting stent (BES) with a sirolimus-eluting stent (SES).Methods: Among 1,707 patients enrolled in the prospective, multi-center, all-comers LEADERS trial, 81 with CTOs were treated with either a BES (n = 45) or a SES (n = 36). The primary endpoint was the occurrence of major adverse cardiac events (MACE): cardiac death, myocardial infarction (MI) and clinically-indicated target vessel revascularization (TVR).Results: At 5 years, the rate of MACE was numerically higher in the CTO group than in the non-CTO group (29.6% vs. 23.3%; p = 0.173), with a significant increase in the incidence of target lesion revascularization (TLR) (21.0 vs. 12.6; p = 0.033), but no difference in stent thrombosis (ST). Patients with CTO receiving a BES demonstrated a lower incidence of MACE (22.2% vs. 38.9%; p = 0.147) with a significant reduction in TLR compared to patients receiving a SES (11.1% vs. 33.3%, p = 0.0214) with an incidence similar to that observed in the non-CTO group treated with BES (11.6%). Definite ST at 5 years nearly halved in the BES group (4.4% vs. 8.3%, p = 0.478) with no ST in the BES group after the first year (0% vs. 8.3%, p for interaction = 0.009).Conclusions: The use of a BES showed a reduction in MACE, TVR, TLR, and ST over time in the CTO subset with similar outcome as for non-CTO lesions