Open positions of CRC 1242

What we offer

Download: Stellenausschreibung deutsch​
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.

A6 (Campen, Tong): Non-Equilibrium Charge Transfer between Solids and Adsorbates in Vacuum and at Electrified Solid/Liquid Interfaces

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.
back to the top

B6 (Meyer zu Heringdorf): Relaxation Pathways for Collective Electronic Excitations

Description

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 top

C3 (Horn-von Hoegen): Driven Phase Transitions at Surfaces: Initial Dynamics, Hidden States and Recovery of Ground State

Description

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 top