In the following, you can find potential summer student projects of the PSI Center for Photon Science. Please see "How to apply" for details on submitting your application for one of the projects.
Scalable laser monitoring for trapped-ion quantum computing
Trapped-ion quantum computing relies on stable laser addressing for cooling and qubit operations. Our experiment houses a 20-zone ion trap array with integrated optical addressing. Many fibers are necessary to deliver the light to the trapped-ion qubits. To improve the long-term stability and up-time of our setup, we need to monitor and counter intensity drifts in all of them. In this project, you will set up fiber optics, photodetectors, and electronics for online monitoring of our lasers and program a feedback system to correct for fast and slow drifts in order to improve our qubit operations.
Area of study: Quantum Information, Atomic Physics, Lasers
Required technical skills:
- Python and Grafana/influxdb
- Basic electronics
- Fiber and free-space optics and lasers
- FPGA programming
Desired background/domain knowledge/experience/interests:
- Fundamentals of quantum physics / AMO physics
- Systems monitoring
- Control technology (using digital PID controllers)
What you (the student) will learn:
- Design of optical / fiber setups
- Operation of quantum computing experiments
- Setting up control loops for laser stabilization
Contact person: Julian Schmidt (julian.schmidt@psi.ch)
Improving 3D X-ray imaging using machine learning
In this project you will explore the use of machine learning and artificial intelligence to improve reconstructions from X-ray computed tomography. Emphasis will be given to sparse measurements and recovery of missing data using advanced algorithms, and in particular for nano-scale imaging of tissues and integrated circuits. Most of the work will involve programming and developing algorithms with opportunities to help during X-ray experiments.
Area of study: Physics, Computer Science
Required technical skills:
- Python (essential), Matlab (useful)
- Physics and imaging knowledge (useful)
This position will suit you if you:
- Enjoy programming and developing your own computational tools. Eg. functions and custom algorithms have to be implemented to interface experimental data.
- Have experience with programming projects
- Are interested in imaging, and physical principles of imaging.
- Value working in a diverse, multicultural, international environment.
What you (the student) will learn:
- Tools for tomographic reconstruction
- Apply machine learning to advanced 3D imaging
Contact person:
Prof. Dr. Manuel Guizar-Sicairos, Computational X-ray Imaging Group, manuel.guizar-sicairos@psi.ch
Crystallisation of photoactive proteins for time-resolved crystallography
Time-resolved serial femtosecond crystallography (TR-SFX)1,2 is a powerful technique that can reveal, at near-atomic resolution, how the structure of proteins change as they carry out their biological function. Although this technique can offer incredible insight into protein function, the practical aspects of TR-SFX experiments are complex and, as such, can have a strong influence on data quality and interpretation. We would like you to help us develop a set of standard protein crystal samples that can be used to benchmark and then further develop TR-SFX methodology at the Swiss X-ray free electron laser (SwissFEL). The ultimate goal is to use these samples to define experimental conditions that deliver optimum data quality. The project would involve cloning, expression and purification of a series of photoactive proteins. The crystallisation of the successfully purified proteins then needs to be thoroughly characterised. The project will primarily involve laboratory work in a biochemistry setting and would suit someone with strong attention to detail who enjoys practical work.
Area of study: Biochemistry, biophysics, biology, chemistry
Required technical skills:
- Laboratory experience (biology/biochemistry/chemistry) – candidates should be comfortable pipetting and making chemical solutions
Desired background/domain knowledge/experience/interests:
- Understanding of molecular biology
- Understanding of recombinant protein expression and purification
- Interest in structural biology
- Interest in X-ray crystallography
What you (the student) will learn:
- Molecular biology (cloning and mutagenesis)
- Recombinant protein expression using E.coli
- Protein purification and characterisation
- Protein crystallisation
- Sample delivery methods for TR-SFX experiments
Contact person: Emma V. Beale (emma.beale@psi.ch)
1 - Brändén, G. and Neutze, R. Advances and challenges in time-resolved macromolecular crystallography. Science 373, eaba0954 (2021). DOI:10.1126/science.aba0954
2 - Barends TRM, Stauch B, Cherezov V, Schlichting I. Serial femtosecond crystallography. Nat Rev Methods Primers 2:59 (2022). DOI:10.1038/s43586-022-00141-7