General information
A lump sum of CHF 600.- for transportation expenses’ support will be given to each student doing his/her semester project in AQUA in Neuchâtel.
A lump sum of CHF 1600.- for transportation expenses’ support will be given to each student doing his/her Master project in AQUA in Neuchâtel.
Doing a part of the project in Lausanne can be discussed. The lump sum would then be adapted proportionally to the number of trips to Neuchâtel.
No refund of effective fees will be provided. We advise students coming to do a project in Neuchâtel to buy a half-fare subscription.
Master projects
Single-photon sensitivity, picosecond temporal resolution and CMOS integration makes single-photon avalanche diode (SPAD) arrays desirable for 3D imaging applications including light detection and ranging (LiDAR), fluorescent lifetime imaging (FLIM), quantum key distribution (QKD) and positron emission tomography (PET). InGaAs/InP based SPADs are promising to be used in longer wavelengths for which silicon based SPADs are inefficient due to their higher bandgap. On the other hand, using InGaAs/InP detectors instead of CMOS integrated SPADs brings challenges including 3D integration and higher noise.
At AQUA lab we are developing a hybrid sensor which consists of a CMOS readout integrated circuit (ROIC) bonded to InGaAs/InP SPADs to be used for various 3D imaging applications. The project focuses on the setup of the testing environment of the ROIC which includes the printed circuit board (PCB) and FPGA coding. This will be followed by measurements with the 3D bonded sensor to characterize the SPAD array and imaging experiments. The project can be adapted as a semester project or a master’s thesis.
Tasks:
- Literature review to understand the principles of SPADs and readout circuits.
- Design of a new PCB for the ROIC taking the previous one as a reference.
- FPGA firmware design using Verilog/VHDL to control the ROIC and test its functionality.
- SPAD array characterization, LiDAR/3D imaging measurements.
Type: Can be adapted for a semester or Masters project.
Location: Microcity Neuchatel
Contact: Halil Kerim Yildirim [email protected]
Description and contact info can be found here.
Contact: Paul Mos
Description and contact info can be found here
Contact: Paul Mos
Motivation
Single-photon detectors and nanoscale superconducting devices are two major candidates for realizing and supporting quantum technologies. Superconducting nanowires single-photon detectors (SNSPDs) in particular, cover various applications that evolved in the quantum field for the past few years such as high-rate and long-distance quantum key distribution, satellite laser ranging, long-distance imaging and non-quantum applications like molecular spectroscopy. However, the largest SNSPD array reported so far is the kilo-pixel array. One of the main constraints to achieve
high levels of scaling in these detectors is the limited power budget available within the cooling system.
The architectures demonstrated so far, based mainly on analog implementations [1], [2], [3], are promising. However, going beyond one thousand pixels, while maintaining low jitter, low dark counts, high efficiency, and high-count rate is really challenging. For this reason, more innovation is required to scale up SNSPD arrays.
Description
The master project consists on the design and analysis of a low power readout circuit to interface SNSPDs. The project will consist of three main phases:
- Study and understanding of the physics behind Superconducting detectors. In the first months, Simulations using Cadence and SPICE will be conducted to deeply understand the main limitations from an analog design perspective.
- Design. The student will come up or contribute in building up new ideas for a single pixel readout.
- Testing. The student will help in the test of some building blocks at cryogenic temperatures as well as the realization of prototypes that may be patented.
Tasks
- Literature research.
- Detailed analysis of the SNSPD-pixel interface on Cadence.
- Electromagnetic analysis of the device using ADS.
- Design of prototypes on Altium.
- Cryogenic Analog and Digital interface testing.
[1] Emma E. Wollman et al., “Kilo pixel array of superconducting nanowire single-photon detectors,” Opt. Express 27, 35279-35289 (2019).
[2] Zhao et al. “Single-photon imager based on a superconducting nanowire delay line,” Nature Photon 11, 247–251 (2017).
[3] S. Doerner et al., “Frequency-multiplexed bias and readout of a 16-pixel superconducting nanowire single photon detector array,” Appl. Phys. Lett. 111(3), 032603 (2017).
Supervisor: Jad Benserhir, Prof. Edoardo Charbon
Location: EPFL in Microcity, Neuchâtel
Starting date: TBD
Contacts: [email protected]
The goal of the project is to demonstrate efficiency improvement at wavelengths below 900 nm by comparing the single photon efficiency spectrum of two InGaAs/InP SPADs with and without substrate. For this purpose student should fabricate these devices in CMi (Center of Micronanotechnology) by following various photolithography, etching, metallization and thinning processes. Following the fabrication, devices should be placed on a PCB and characterized for their photon detection efficiency. The student will have a chance to experience/perform all of the fabrication process of a single photon avalanche detector from scratch and set up an experiment to analyze the performance of the detector.
This project can be adapted as a semester or Master project.
Contact: [email protected]
Projects description and contact info can be found here.
Contact: David Rodríguez Martínez
Semester projects
The goal of the project is to demonstrate efficiency improvement at wavelengths below 900 nm by comparing the single photon efficiency spectrum of two InGaAs/InP SPADs with and without substrate. For this purpose student should fabricate these devices in CMi (Center of Micronanotechnology) by following various photolithography, etching, metallization and thinning processes. Following the fabrication, devices should be placed on a PCB and characterized for their photon detection efficiency. The student will have a chance to experience/perform all of the fabrication process of a single photon avalanche detector from scratch and set up an experiment to analyze the performance of the detector.
This project can be adapted as a semester or Master project.
Contact: [email protected]