Careers

You will use laser-induced electron diffraction to image the ultrafast elementary steps of chemical dynamics of "everyday (bio)chemistry", at thermal-energy scales similar to room temperature, with atomic resolution. The research builds on cutting-edge controlled-molecule preparation and imaging techniques available in our group our experience with ultrafast lasers. It is in close connection with the Theory team of our group and collaboration partners in Hamburg and Berlin. This project is part of the federal cluster of excellence Center for Ultrafast Imaging. Link to the announcement, deadline for applications 2024-02-15

We have an open position to work on novel sample preparation and control concepts for structural biology at x-ray free-electron lasers (XFELs) and electron-microscopy (EM) facilities. You will implement and advance techniques to shock-freeze solvated biological macromolecules to image and characterize these samples, to implement control techniques such as species selection and laser alignment, and to exploit the controlled biomolecular samples in single-particle diffractive-imaging experiments, e.g., at free-electron lasers. This work focuses on developing and implementing experimental methodology that allows for the spatial separation of macromolecular conformers in sample-injection pipelines for XFEL experiments.

The Controlled Molecule Imaging group at CFEL, DESY has an open PhD position in a research project that studies the ultrafast light-induced dynamics of model chromophores in size-controlled water clusters. This project aims to investigate how different-sized chromophore-water clusters can be separated to examine the influence of successive water molecule additions on the dynamics of biologically relevant systems. The research builds on and advances the cutting-edge solvated-molecule preparation and imaging techniques available in our group and our collaborators' experience with ultrafast lasers. This project is part of the HELIOS graduate school and is in close collaboration with Francesca Calegari in Hamburg and partners in Lund (Per Johnson and Mathieu Gisselbrecht).
Link to the announcement, deadline for applications 2024-02-26

Within this project, you will use newly developed sources for cold nanoparticles and bio-molecules, such as cryogenic buffer-gas cells, and develop advanced methods to strongly control these systems. The shock-frozen, cold samples emitted from the buffer-gas cell can be further controlled using strong inhomogeneous electric fields. This allows one to select single structural isomers, i.e., different structural arrangements such as folded vs. globular proteins, based on their distinct interactions with the field. Furthermore, in combination with strong ac electric or laser fields these systems can be aligned and oriented in space, rendering the individual molecules practically identical even in laboratory space. The developed experimental setups will be employed for novel diffractive-imaging experiments, both at FEL facilities as well as in laboratory based setups.

We are specifically searching for a strong doctoral candidate to investigate the selection and control of biological macromolecules with external electric fields. This should result in purified and controlled samples for ultrafast, femtesecond diffractive-imaging experiments at XFELs in order to unravel the elementary initial steps of biochemical processes.

Please submit your application as a single PDF file containing, at least,

• A brief letter of motivation (max. 1 page)
• Your curriculum vitae
• A list of 3–5 most important publications and your OrcID
• The names and contact information of 2-3 persons who can serve as references

For further inquiries, please contact us at office.kuepper@cfel.de.

CMIdaq is a new implementation of a distributed controls and data acquisition system for Controlled Molecule Imaging experiments. The system is based on Tine and developed in Python and Qt. Hardware includes high-speed high-resolution cameras, fast digitizers and oscilloscopes, timing distribution and time delay electronics, motors for many different pieces of equipment, various laser sources, Linux, Windows, and Mac OS X computers, etc. Data handling and storage includes the use of gpfs (IBM Spectrum Scale) and dCache.

In this project, a modern, user-friendly, flexible, yet easy to use graphical user interface shall be designed and developed. This includes the implementation of modern UI concepts, versatile online analysis tools, data storage and documentation tools, and an analysis of user feedback.

Contacts: Prof. Dr. Jochen Küpper

These novel experimental approaches are supported by computational simulations based on classical trajectory calculations in combined electric and laser fields. To allow for the simulation of optical manipulation of nano-objects and very large biological objects, such as viruses or protein complexes, we are extending our computation suite to include new models of the underlying physics as well as the experimental apparatus used.

We offer an undergraduate thesis project to extend our simulation framework CMIfly and to implement new-physics descriptions in the simulation codes.

A successful candidate will have a strong background in modern software development. Experience in physics, hydrodynamics, and optics as well as in numerical methods is a plus.

We offer unique research opportunities in an interesting and open team and with first-class experimental and computational facilities. Our group is embedded in the Center for Free-Electron-Laser Science, DESY, the University of Hamburg and the excellence cluster Hamburg Center for Ultrafast Imaging.

J. Chem. Phys. 131, 064309 (2009))
Int. Rev. Phys. Chem. 34, 557 (2015)
IPhys. Rev. Applied 4, 064001 (2015)

Contacts: Prof. Dr. Jochen Küpper

We are developing a general-purpose code for the description to the rotational motion of arbitrarily complex molecules in electric and laser fields. The code implements a numerical solution to the time-dependent Schrödinger equation of the system considering all relevant symmetries. Typical runtimes for complex molecules in strong fields are many CPU months.

Here, an efficient and general parallelization shall be implemented. In the first step, this should be done through a multithreading approach, partly using multithreaded BLAS routines and partly by direct manual parallelization at higher levels. Further steps include message-passing parallelization across compute nodes as well as GPU-based acceleration.

The quantum-physics developments of the code are performed in close collaboration with Rosario González Férez at the Universidad de Granada. See CMIstark for a implementation of a time-independent dc-electric-field-only subset of the problem.

Contacts: Prof. Dr. Jochen Küpper

The Controlled Molecule Imaging group at the Center for Free-Electron Laser Science at DESY and University of Hamburg performs novel experiments on the control and imaging of gas-phase molecules and their intrinsic ultrafast dynamics. We develop unique experimental approaches to record movies of molecules at work.

These novel experimental approaches are supported by computational simulations based on solutions of the time-dependent Schrödinger equation. To increase the accessible molecular complexity in these simulations we are implementing and improving parallelized solvers in our codes.

We offer a bachelor thesis project to perform an extended runtime analysis and implement corresponding performance improvements and significant parallelization of our TDasyrot program suite.

A successful candidate will have a strong background in modern software development. Experience in quantum physics, numerical methods, and massive parallelization are a plus.

We offer unique research opportunities in an interesting and open team and with first-class experimental and computational facilities. Our group is embedded in the Center for Free-Electron-Laser Science, DESY, the University of Hamburg and the excellence cluster Hamburg Centre for Ultrafast Imaging.

Phys. Rev. Lett. 102, 023001 (2009)
Comp. Phys. Comm. 185, 339 (2014)
Phys. Rev. Lett. 114, 103003 (2015)

Contacts: Prof. Dr. Jochen Küpper

In this project a next-generation particle trajectory simulator shall be developed. Based on experience from two earlier codes to describe trajectories on particles through electric fields, we wish to implement a general purpose computational framework and user interface to describe the motion of large numbers of molecules and particles through laser and electric fields. From a physics point of view, various different interactions between the molecules and particles have to be included; sometimes taking care of the back-action of the particle on the field. Moreover, particle-particle interactions as well as particle-background interactions are relevant in certain cases.

This code forms the heart of the modeling of our control experiments and is of greatest importance for the prediction of future experiments and experimental setups. Furthermore, computation times can be very high and efficient use of resources (CPU, memory), parallelization, and appropriate approximations need to be implemented.

Contacts: Prof. Dr. Jochen Küpper

The Controlled Molecule Imaging group at the Center for Free-Electron Laser Science at DESY and University of Hamburg performs novel experiments on the control and imaging of gas-phase molecules and their intrinsic ultrafast dynamics. We develop unique experimental apparatus to record movies of molecules at work.

Novel experimental setups require new software to control equipment, acquire data, and analyze the obtained results. To strengthen our team we are looking for software developers with a background in experiment controls, data acquisition, and online analysis — or the desire to apply modern programming concepts to these important and challenging applications.

A successful candidate will have a strong background in modern software development and hardware programming. Experience in experimental physics or related scientific environments is a plus but not necessary. The position can be filled at various levels.

We offer unique research opportunities in an interesting and open team and with first-class experimental and computational facilities. Our group is embedded in the Center for Free-Electron-Laser Science, DESY, the University of Hamburg and the excellence cluster Hamburg Centre for Ultrafast Imaging.

Phys. Rev. Lett. 100, 133003 (2008)
Phys. Rev. Lett. 102, 023001 (2009)
Angew. Chem. Int. Ed. 48, 4900 (2009)
Nature Phys. 6, 428 (2010)
Science 342, 98–101 (2013)
Phys. Rev. Lett. 114, 103003 (2015)

Contacts: Prof. Dr. Jochen Küpper