PhD scholarship in Moiré and Patterned 2D Materials for Bandgap Engineering - DTU Physics

If you want to design the electronic properties of a material rather than simply measure them, this PhD puts the tools in your hands. When two-dimensional crystals are stacked with a controlled twist, or when a periodic pattern is imprinted into them, an artificial superlattice emerges in which the band structure can be reshaped and bandgaps opened by design, using a novel combination of 2D materials and freestanding oxide membranes. You will create such materials yourself in a group that has worked with 2D materials for two decades and with full access to the cleanroom and microscopy infrastructure at DTU Nanolab. The project is part of METRIQS and is carried out together with national and international partners.

Responsibilities and qualifications Your overall focus will be to create and control superlattices in graphene and other 2D materials, and to establish how the engineered structure translates into an engineered electronic band structure. You will pursue two complementary routes: assembling hybrid van der Waals heterostructures in which the moiré periodicity is set by twist angle and lattice mismatch and imprinting periodic patterns directly into the 2D material or its supporting layers by nanofabrication. Both routes call for careful design, reproducible processing and close comparison between intended and realised structure. You will work with colleagues at DTU Physics and DTU Nanolab and with partners in the METRIQS collaboration. Your primary tasks will be to:

• Design superlattice geometries and device layouts, using modelling and simulation to decide what is worth fabricating.
• Assemble hybrid van der Waals heterostructures from graphene, hBN, transition metal dichalcogenides and related materials with controlled twist and alignment, using a newly developed semi-automatic stacking system, and collect data on stacking recipes and results to obtain and document optimal parameters through datamining and statistics.
• Imprint periodic patterns into 2D materials and their supporting layers using electron beam lithography, etching, thin film deposition and related nanofabrication.
• Fabricate devices in which the engineered materials can be contacted, gated and measured.
• Characterise structure and electronic properties by scanning probe microscopies, electron microscopies, Raman spectroscopy, optical spectroscopy and electrical transport at cryogenic temperatures.
• Connect the measured electronic response back to the intended superlattice design, and iterate on the design.
• Establish reproducible fabrication and measurement protocols, analyse your data and present the results in publications and at conferences.

• A letter motivating the application (cover letter)
• Curriculum vitae
• Grade transcripts and BSc/MSc diploma (in English) including official description of grading scale

You may apply prior to obtaining your master's degree but cannot begin before having received it. Applications received after the deadline will not be considered. All interested candidates irrespective of age, gender, disability, race, religion or ethnic background are encouraged to apply. As DTU works with research in critical technology, which is subject to special rules for security and export control, open-source background checks may be conducted on qualified candidates for the position.DTU Physics conducts research across a broad range of fundamental and applied physics. The position will be based in the department's 2D Materials Physics and Engineering section (2DPHYS), where we study the synthesis, fabrication and physical properties of atomically thin materials and heterostructures, including also hybrid heterostructures. The project makes extensive use of the nanofabrication and characterisation facilities at DTU Nanolab and involves close collaboration with national and international research partners in METRIQS.DTU – For the benefit of society since 1829DTU is one of Europe's leading elite technical universities. Through research and education at an international top level, we create solutions to the major societal challenges of our time and help secure Europe's global leadership in sustainable technological development. Since Hans Christian Ørsted founded DTU almost 200 years ago, our mission has remained the same: We develop and create value through the natural and technical sciences for the benefit of society. DTU has 13,800 students, 1,600 PhD students, and 6,500 employees. We work in an international environment and have an inclusive, stimulating, and informal work culture. DTU has campuses in all parts of Denmark and in Greenland and collaborates with the best universities around the world.