PhD position :Integrated electro optical modulators and photodetectors in the mid-IR spectral range.

Organisation/Company

Centre de Nanosciences et de Nanotechnologies

Department

Photonics

Research Field

Physics

Researcher Profile

First Stage Researcher (R1)

Country

France

Application Deadline

28 Apr 2024 – 00:00 (UTC)

Type of Contract

Temporary

Job Status

Full-time

Is the job funded through the EU Research Framework Programme?

HE / ERC

Reference Number

101097569

Is the Job related to staff position within a Research Infrastructure?

No

Offer Description

Mid-infrared (mid-IR) spectroscopy is a nearly universal way to identify chemical and biological substances and to perform non-intrusive diagnostics. Indeed, the mid-IR spectral range contains the so-called “fingerprint” region (wavelength from 6 to 15 µm) in which most molecules have vibrational and rotational resonances. This wavelength range can, hence, be exploited to detect small traces of environmentally hazardous and toxic substances for a variety of applications including defense, security and industrial monitoring. A challenging task is to make mid-IR spectroscopy accessible in remote areas, driving the development of compact and cost-effective solutions to replace table-top systems.

            The development of mid-IR photonics circuits thus benefited from a burst of research activity in the recent years. Different solutions are explored for the development of an integrated mid-IR sensing platform. Among them silicon (Si) photonics can have a major impact for the development of mid-IR photonics by leveraging the reliable and high-volume fabrication technologies already developed for microelectronic integrated circuits. As a key point for optical spectroscopy and molecular sensing, the optical functions that will be developed using Si photonics circuits should offer the capability of retrieving the spectrum of a light beam after interaction with the substance to be analyzed, to detect the presence and quantify the concentration of the molecular compounds.

            Ge-rich SiGe photonics has been developed in our group in the recent years, in strong collaboration with Politecnico Di Milano. It has been demonstrated that graded index SiGe waveguide can be used in a large wavelength range in the mid-IR, and a large range of passive building bloc including Mach Zehnder interferometers or integrated resonators have been obtained. Then, the demonstration of large bandwidth optical source on chip based on non-linear optical effects of SiGe waveguides, and the realization of optoelectronic devices (modulator and photodetector) recently completed the photonics platform. For the moment the performance of the modulator and photodetector are limited in comparison with devices operating in the near infra-red range, especially the modulator extinction ratio. This comes from a compromise between the modulator loss and efficiency in the Schottky-based or PIN-based devices developed up to now.

In this context, the goal of the PhD is to develop high performance integrated modulator and photodetector, operating in a wide spectral range in the mid-infrared, typically from 5 to 12 µm wavelength.

Different strategies will be employed, including the tuning of electrical and optical confinement in the modulator, the development of new diode architecture, as well as the proper design of RF access.

The research activity will include:

– Modeling of the photonics devices (optical, electro-optical simulation using commercially available software and developing code interfaces (python/matlab)

– Design and fabrication of the devices in in-house clean room

– Experimental characterizations of the devices, using a mid-IR optical bench already developed in the group

The work is done in the framework of EU ERC Electrophot project (2023-2028), in collaboration with Politecnico Di Milano.

Requirements

Research Field

Physics

Education Level

Master Degree or equivalent

Languages

ENGLISH

Level

Excellent

Additional Information
Work Location(s)

Number of offers available

1

Company/Institute

C2N/Université Paris Saclay

Country

European Union

Geofield

Where to apply

E-mail

[email protected]

Contact

State/Province

France

City

Palaiseau

Website

https://www.c2n.universite-paris-saclay.fr/en/

Street

10, Boulevard Thomas Gobert

Postal Code

91120

STATUS: EXPIRED