Integrated bolometric photodetectors based on transparent conductive oxides from near- to mid-infrared wavelengths

On-chip photodetectors are essential components in optical communications as they convert light into an electrical signal. Photobolometers are type of photodetector that functions through a resistance change caused by electronic temperature fluctuations upon light absorption. They are widely used in the broad wavelength range from UV to MIR and can operate on a wide material platform. In this work, I introduce a novel waveguide-integrated bolometer that operates in a wide wavelength range from NIR to MIR on the standard material platform with the transparent conductive oxides (TCOs) as the active material. This material platform enables the construction of both modulators and photodetectors using the same material, which is fully CMOS compatible and easily integrated with passive on-chip components. The photobolometers proposed here consist of a thin TCO layer placed inside the rib photonic waveguide to enhance light absorption and then heat the electrons in the TCO to temperatures above 1000 K. This rise in electron temperature leads to decreasing electron mobility and consequential electrical resistance change. In consequence, a responsivity exceeding 10 A/W can be attained with a mere few microwatts of optical input power. Calculations suggest that further improvements can be expected with lower doping of the TCO, thus opening new doors in on-chip photodetectors.Comment: 16 pages, 7 figure

Transparent conductive oxides as a material platform for photonic neural networks

Photonics integrated circuits have a huge potential to serve as a framework for a new class of information processing machines and can enable ultrafast artificial neural networks. They can overcome the existing speed and power limits of the electronic processing elements and provide additional benefits of photonics such as high-bandwidth, sub-nanosecond latencies and low-energy interconnect credentials leading to a new paradigm called neuromorphic photonics. The main obstacle to realize such a task is a lack of proper material platform that imposes serious requirements on the architecture of the network. Here we suggest and justify that transparent conductive oxides can be an excellent candidate for such a task as they provide a nonlinearity and bistability under both optical and electrical inputs.Comment: 13 pages, 7 figure

Illustrer les Grandes Chroniques de France vers 1400 : le manuscrit Palais des Arts 30 de la Bibliothèque municipale de Lyon (Tome 2 : annexes)

Annexes du mémoire du Master 2 Cultures de l\u27écrit et de l\u27image portant sur l’étude codicologique du manuscrit Palais des Arts 30 de la bibliothèque municipale de Lyon

CMOS-Compatible titanium nitride for on-chip plasmonic Schottky photodetectors

Here, we propose a waveguide-integrated plasmonic Schottky photodetector (PD) operating based on an internal photoemission process with a titanium nitride plasmonic material. The theoretically examined structure employs an asymmetric metal–semiconductor–metal waveguide configuration with one of the electrodes being gold and the second being either gold, titanium, or titanium nitride. For the first time, we measured a Schottky barrier height of 0.67 eV for titanium nitride on p-doped silicon, which is very close to the optimal value of 0.697 eV. This barrier height will enable photodetection with a high signal-to-noise ratio when operating at a wavelength of 1550 nm. In addition to the measured optical properties of high absorption losses and reasonably large real part of the permittivity that are desired for this type of PD, titanium nitride is also compatible with easy integration on existing complementary metal–oxide–semiconductor technology. The use of titanium nitride results in a shorter penetration depth of the optical mode into the metal when compared to Ti, which in turn enhances the probability for transmission of hot electrons to the adjacent semiconductor, giving rise to an enhancement in responsivity