PhD position in oxide thin film growth and advanced control on polar textures in epitaxial heterostructures

The Nonlinear optics for Epitaxial growth of Advanced Thin films (NEAT) laboratory within the institute of Multifunctional Ferroic Materials in the Materials Department is seeking for PhD candidates. We work on the epitaxial deposition of functional oxide thin films using pulsed laser deposition. We use in-situ diagnostic tools during the growth process to advance the design of technologically relevant oxide thin films. In particular, the combination of state of the art non-linear optics monitoring and electron spectroscopy in situ allows investigating the dynamics of the functional properties as we grow the films from the very first unit cell. We are interested in studying the evolution of physical properties of epitaxial thin films in the ultrathin regime and in the investigation of interface related phenomena in multilayers.

Light-matter interaction is a ubiquitous phenomenon in condensed matter science: It is a prerequisite for elasto-, electro-, and magneto-optical effects that has established light as a versatile, non-invasive probe for functional materials. As a result, optical characterization techniques have significantly contributed to our understanding of the physics governing functional properties of technology-relevant electrically and magnetically ordered materials. Conversely, taking advantage of lightmatter interaction to achieve a remote optical control of such order parameters has been much less explored, especially in technology relevant ferroelectric thin films. This obstructs the development of all-optical control of energy-efficient devices for a new generation of ultrafast nanoscale oxide electronics. The PhD project unites our leading international expertise in oxide thin film growth and nonlinear laser spectroscopy. We will pioneer the study of reversible optical control of spontaneous electrical polarization in our ferroelectric thin films.

The goal of the doctoral project is to explore optical control of polarization in various oxide-based epitaxial heterostructures. Using our unique capacity to engineer oxide thin films interfaces with atomic precision, combined with our state of the art non invasive optical probe of polarization in thin films, we will advance the understanding of the optical manipualtion of polar textures in epitxial systems. By engineering defect concentration, electrostatic boundary conditions at the interface and epitxial strain, we will establish a reversible and robust optical handle on the polarization. This may expend to the remote control of ferroelectric field effects in advanced multiferoic and magnetoelectric types heterostructures.

Our in-situ monitoring capacity of polarization during the growth and now, during optical poling is unique in the world. This PhD project thus offers plenty of room for exciting physics and groundbreaking discoveries, and our lab has exactly the expertise to acquire these. Our intense collaboration with experts in the field of electron microscoy, magnetic characterization and nitrogen vacancy scanning electrometry enable a multiscale apporach.

Candidates will join our international NEAT research team of highly motivated PhD and Master students and use our workplaces for thin films growth and characterization with nonlinear laser spectroscopy. They will design and set up their own experiment and are never afraid to tear it down and try a new approach, should this become necessary. Despite the focus on thin-film growth experiments, the involvement of other experimental techniques and in-depth discussion with theoretical groups are likely.

• You have a masters degree in Physics or Materials Science
• You have basic education in condensed-matter physics
• You like to work on complex problems with an urge to understand phenomena at their roots
• You are highly motivated, self-organized, creative, and used to thinking sideways
• You are a team player who likes to work in an interdisciplinary environment at the interface between optics and condensed-matter physics
• You are communicative with the ability to explain your project to non-specialists in simple words

• Outstanding lab facilities with pulsed laser depostion chambers, femtosecond and nanosecond laser systems
• An international environment of mutually supportive people
• A flat hierarchy: everyone's opinion weighs the same in scientific discussions
• Excellent working conditions and an internationally competitive salary
• Support for attending international conferences and workshops
• An extensive network of scientific collaborators
• Access to the excellent technological infrastructure of ETH Zurich
• Administrative support