Open positions of CRC 1242
You will be a key player in one of the scientific projects of the CRC 1242 and will do research in a highly cooperative and excellent scientific environment. We provide you with research experience in an international context and ensure that you develop scientific independence and the skills to work successfully in a team. In addition, the Integrated Research Training Group (IRTG) will help you to develop the skills necessary for a future career in academics or industry.
Since several types of activities organised by the graduates among themselves act as catalysts for team building, participation in these also will allow you to develop and test your self-reliance. Moreover, the IRTG supports a one-month exchange visit to a partner laboratory abroad during the course of your PhD work.
What we expect
Aside from excellent performance in your studies, we anticipate that you have a great enthusiasm for science and a keen interest in attaining research goals. Furthermore, we expect your participation in the joint organisation of the IRTG and its activities, such as workshops, training courses and presentations
How to apply
Send your application form and your CV to Prof. Jürgen König. Qualified Master of Science or comparable degree (i.e. 4 years of studies) required.
Salaries are according to the TV-L scale up to 75% of level E13.
Description
The project offers PhD positions in two areas of experimental condensed matter physics: time-resolved transport spectroscopy and high-resolution resonance fluorescence measurements, which are closely related and gain knowledge from each other. One PhD position investigates the dynamics of electron tunneling from a two-dimensional electron reservoir into a model system for quantized states in the solid state: self-assembled quantum dots. Using electrical transport spectroscopy measurements, the PhD student will study the quantized state, its wave functions and its evolution from non-equilibrium to equilibrium; this will provide access to a more detailed understanding of electron (spin) dynamics, few-particle interactions and correlations in a highly controllable quantum system. The other PhD position uses resonance fluorescence on a single self-assembled quantum dot to study different non-equilibrium electron (spin) dynamics with outstanding energy resolution, enabling dynamical quantum measurements with unprecedented precision. This puts this project at the forefront of measurements of electron scattering from a confined system into the continuum and quantum measurements of electron dynamics with real-time resolution, where each quantum jump in a dynamical quantum system is measured and analysed by statistical methods. The project has strong collaborations with other projects in the CRC, for example with A02, B03 and B07 on electron transport, counting statistics, quench dynamics and the quantum Zeno effect.Desired skills and experience
A degree in physics (experimental physics) is required, preferably with a background in condensed matter physics, quantum transport or quantum optics. Depending on the research area, an interest in sophisticated high-resolution optical measurements or in transport measurements, involving sample processing in a clean-room environment. back to the topDescription
We are pleased to announce a PhD position for a highly motivated and talented individual to join our dynamic research team at the Faculty of Physics of the University Duisburg-Essen. We are seeking a candidate who is passionate about investigating the non-equilibrium properties of complex materials with a focus on electronic and lattice degrees of freedom and their interaction. The project will involve studying the behavior of complex materials such as metal-insulator heterostructures, spin-crossover complexes, and transition metal dichalcogenides. The primary objective is to address the challenge of distinguishing electronic and lattice degrees of freedom in these materials. By utilizing a combination of near edge and extended x-ray absorption fine structure analysis in the time domain, we aim to explore unique opportunities for understanding these properties under non-equilibrium conditions. The successful candidate will join beamtimes at cutting-edge facilities such as the FemtoSpex beamline at BESSY II and the Spectroscopy & Coherent Scattering instrument at the European X-FEL, Hamburg, which provide femtosecond soft x-ray pulses. Additionally, our table-top setup in Duisburg will offer complementary opportunities, including the generation of soft x-ray pulses through high-harmonic generation in noble gases using infrared light pulses.Desired skills and experience
- A strong academic background with a Master's degree (or equivalent) in Physics, Chemistry, Materials Science, or a related field.
- Proficiency in experimental techniques and methods related to spectroscopy and/or condensed matter physics.
- Familiarity with computational tools and data analysis techniques.
- Excellent problem-solving and analytical skills.
- Effective communication and collaboration abilities.
- A passion for scientific research and a strong desire to contribute to the advancement of knowledge in the field of complex materials.
Description
Van der Waals heterojunctions, particularly the interface between transition metal dichalcogenides (TMDCs) and organic molecular matter, hold the promise of enabling a new generation of transistors, ultrafast photodiodes and photovoltaic cells. Realizing the best version of such devices physics allows requires understanding exactly how electrons move across the junction. Because both the TMDC and organic phases typically stabilize a rich variety of quasiparticles (excitons, trions, etc.), understanding the transfer mechanism requires insight into quasiparticle lifetimes and relaxation mechanisms both within each bulk phase and across the interface. We seek a motivated PhD candidate to investigate non-equilibrium charge transfer in one such system: MoS2/oligo-acene junctions. Conventional characterization of such systems, e.g. transient UV/Vis absorption, faces challenges in disentangling charge carrier dynamics occurring in adjoining bulk phases from those occurring at the interface. To overcome this challenge the envisioned PhD project will employ laser-based, even order, nonlinear optical tools (principally ultrafast time resolved sum frequency spectroscopy and second harmonic microscopy). As we and others have shown in recent work this toolbox allows the possibility quantitatively separating charge carrier dynamics in either bulk phase from that occurring at the interface and thus offers insight into charge transfer mechanism not possible by other means. The position offers access to state-of-the-art facilities, opportunities to present at conferences, and publish in high-impact journals.
Desired skills and experience
- A degree in experimental Physics, Physical Chemistry or a related field is required
- Candidates with a background in photonics, spectroscopy, photovoltaic devices, or ultrafast phenomena – as demonstrated in course work and prior research projects – will be preferred.
- Candidates with demonstrated proficiency in managing and maintaining extensive experimental setups will be preferred.
Description
We are looking for an early career researcher to join our team investigating ultrafast, optically induced dynamics in perovskite oxide heterostructures as a PhD student or postdoctoral researcher. The candidate will perform preparation of oxide samples by pulsed laser deposition and their characterization by in-house methods as well as x-ray absorption spectroscopy at synchrotron sources. Time-resolved x-ray absorption spectroscopy at free electron lasers will then be used to analyze the charge carrier and lattice dynamics after optical pumping, based on our previously developed methods: L. Le Guyader et al., J. Synchrotron Rad. 30, 284 (2023); T. Lojewski et al., Mat. Res. Lett. 11, 655 (2023). A particular focus lies on manipulating the material response through a systematic variation of material properties and tunable pump excitation. The project is integrated in a close collaboration between two research groups with a strong expertise on static and time-resolved x-ray absorption spectroscopy at large scale facilities, allowing the candidate to develop scientific skills in oxide preparation and characterization, (time-resolved) x-ray spectroscopy including data analysis and modelling, and pump-probe experiments. A postdoctoral researcher will furthermore have the option to develop their scientific leadership through the development and execution of their own beamtime proposals, and to join the collaborative in-house development of time-resolved x-ray absorption spectroscopy at a high harmonic generation source operated by project A05.Desired skills and experience
PhD student position: We are looking for a highly motivated candidate with a strong interest in condensed matter physics and a Master’s degree in physics or a related field. Previous experience with pulsed laser deposition or x-ray spectroscopy will be beneficial, but is not required. PostDoc position: We are looking for a highly motivated candidate with a doctoral degree in experimental physics or a related field, who is aiming to develop and strengthen their scientific expertise on ultrafast dynamics of condensed matter. Previous experience with pump-probe experiments, preferentially time-resolved x-ray absorption spectroscopy or other x-ray methods, is required. We encourage female candidates to apply as we strive to promote gender diversity and equality in our research team.Description
The doctoral researcher shall investigate the dynamics (spin, vibration, exciton) of individual molecules adsorbed on metal and 2D material substrates using low-temperature scanning tunneling microscopy. Time resolutions down to one picosecond are achieved by coupling THz radiations to the STM junction. The doctoral researcher will develop an expertise with time-resolved scanning tunneling microscopy, ultrahigh vacuum and cryogeny technologies, and various associated techniques. Scientifically, he/she will gain knowledge on spin, phonon, and exciton properties of molecules described with quantum mechanics.Desired skills and experience
We are looking for a highly motivated candidate with a degree in physics or in a relevant field. The candidate is expected to have a good command of English and a solid background in nanosciences. Previous experience and knowledge in scanning tunneling microscopy, ultrahigh vacuum, and pump-probe spectroscopy are highly appreciated. back to the topDescription
An experimental analysis of the spatio-temporal correlation of hot electrons propagating in heterostructures using time-resolved photoelectron spectroscopy shall be carried out by this project’s student. The activity comprises preparation and the conduction of first experiments on Fe/Au heterostructures, in which optical excitations in a Fe layer generated by femtosecond laser pulses are analyzed by pump-probe techniques at a different position in space on the Au surface similar to a time-of-flight experiment inside a material. The PhD student will acquire expert knowledge in a variety of fields, including ultrafast laser systems and physics, ultrahigh vacuum technology, surface preparation and characterization methods and photoelectron spectroscopy. He or she will be incorporated into a well established research group that combines expertise in these and other fields in the context of ultrafast science.Desired skills and experience
You should have a degree in physics, laser science or related field and should be interested in challenging, state-of-the-art experimental setups. Knowledge and/or experience in one or more of the above mentioned areas is desired, but by no means necessary. back to the topDescription
We are using (both static and time-dependent) density functional theory for the theoretical description of non-equilibrium states of condensed matter. The prospective Ph.D. student should perform calculations addressing the excitations of two-dimensional materials and of molecular layers adsorbed on them. The investigations are carried out in collaboration with experimental projects in the CRC, comprising both methodological aspects (e.g the efficient description of charge transfer and interlayer excitons in complex systems) as well as prospects for applications, e.g. in hybrid organic-inorganic solar cells. Thereby, the PhD student will develop expertise in modern numerical methods of condensed matter physics and quantum chemistry.Desired skills and experience
A Master in Physics or Theoretical Chemistry is required, preferably with a background in Computational Physics or Chemistry. A keen interest in collaboration with experimental groups and in the development of mathematical models for non-equilibrium phenomena in condensed matter is advantageous.
back to the top
Description
The PhD student shall study the time evolution after a quench/excitation for experimentally relevant model Hamiltonians (e.g., Fermi-Hubbard model), especially in the regime of strong correlations. The goal is the theoretical understanding of the dependence of this temporal evolution on the intrinsic dynamics of the system, the initial conditions (e.g. temperature), and the specific mechanism of excitation or quenching. To this end, mainly analytical methods shall be developed and applied (possibly supplemented by numerical simulations, when appropriate). Thereby, the PhD student will develop expertise with advanced analytical approaches to many-body quantum dynamics.Desired skills and experience
Master in Theoretical Physics, preferably with emphasis on analytical methods. Experience with many-body quantum dynamics (e.g., in solid state physics or optical lattices) are advantageous. back to the topDescription
This challenging experimental PhD project is devoted to the ultra-fast non-equilibrium structural dynamics of the phonon system of surfaces and thin films. Upon excitation of the electrons with fs-laser pulses the lattice system reacts delayed due to electron-phonon coupling on a time scale of a few ps. The dynamics of such processes and the underlying fundamental processes are so far “terra incognita” and will be studied by ultrafast time resolved electron diffraction in a pump-probe setup. As the project relies on several modern experimental methods, the PhD student will gain a profound knowledge in a variety of techniques. Ultrafast reflection high energy electron diffraction (RHEED) with an unmatched temporal resolution of 330 fs together with femtosecond laser pulses form the experimental basis for the project. Samples are in-situ prepared using molecular beam epitaxy. Scientifically, the PhD student will study electron phonon coupling, mode conversion in adsorbate systems, nanoscale heat transport in thin films, and ultrafast phenomena at surfaces of solid state matter.Desired skills and experience
A degree in Physics (experimental physics) is required, preferably with a background in surface science or ultrafast phenomena. A keen interest in dynamics of ultrafast processes at surfaces and surface electron diffraction is needed, along with a talent to manage and maintain extensive experimental setups. back to the topDescription
This challenging PhD project is devoted to nonlinear electron emission triggered by surface plasmon polaritons. Surface plasmon polaritons are longitudinal electron density waves that can be excited by a femtosecond laser pulse and that propagate along the surface of a noble metal. It is the aim to understand the electron emission in the presence of extremely intense plasmonic excitations, and to manipulate the electron emission pathways by forming plasmonic foci both in the presence and absence of nanoparticles. The distinction between light- and plasmon-induced emission processes in time and space is accomplished in a femtosecond time-resolved photoemission microscopy experiment. As the project relies on several modern experimental methods, the PhD student will gain a profound knowledge in a variety of techniques. Low Energy Electron Microscopy and Photoemission Electron Microscopy in conjunction with femtosecond laser pulses form the experimental basis for the project. Samples are prepared using molecular beam epitaxy and focused ion beam milling. In collaboration with project A1, the PhD student will integrate nanoparticles into the plasmonic focusing structures. Scientifically, the PhD student will learn about surface plasmon polaritons, nonlinear electron emission, ponderomotive acceleration of electrons in confined structures, and plasmon-nanoparticle interaction.Desired skills and experience
A degree in Physics (experimental physics) is required, preferably with a background in surface science, plasmonics, or ultrafast phenomena. A keen interest in surface plasmon related phenomena and surface electron microscopy is needed, along with a talent to manage and maintain extensive experimental setups. back to the topDescription
This challenging experimental PhD project is devoted to the ultra-fast non-equilibrium structural dynamics of photo induced phase transitions at surfaces. The initial dynamics of the atoms, the evolution of so-called hidden states and the recovery to the ground state shall be studied by means of ultrafast time resolved electron diffraction in a pump-probe setup. The phd student will contribute to the design and setup of a new ultra-compact diffraction chamber aiming for a temporal resolution of less than 200 fs (FWHM). As the project relies on unique experimental methods, the PhD student will gain a profound knowledge in a variety of modern techniques. Ultrafast reflection high energy electron diffraction (RHEED) with an attempted temporal resolution of less than 200 fs together with femtosecond laser pulses form the experimental basis for the project. Samples are in-situ prepared using molecular beam deposition. Scientifically, the PhD student will become an expert in the fundamental quantum processes which drive a system into a non-equilibrium state when undergoing a phase transition.Desired skills and experience
A degree in Physics (experimental physics) is required, preferably with a background in surface science or ultrafast phenomena. A keen interest in dynamics of ultrafast processes at surfaces and surface electron diffraction is needed, along with a talent to manage and maintain extensive experimental setups. back to the topDescription
Are you looking for an exciting task in science?Would you like to work in a team?
Do you like to communicate?
Do you value reliability and responsibility?
Then we have something for you!
We are a team of scientists trying to solve a tricky problem: We want to know exactly what happens when an ion hits a surface, and for this we need the thinnest samples and the shortest ion pulses world-wide.
Desired skills and experience
If you want to work together with us to achieve these goals, you will ideally hold a degree in physics or related disciplines in science or engineering and experience in one of the following areas: 2D materials, ion-solid interaction, or pump-probe experiments.Curious? Then let's talk! back to the top