Strain engineering in Two-dimensional materials
Event details
| Date | 01.05.2015 |
| Hour | 14:15 |
| Speaker |
Prof. Shu Ping Lau Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China Bio: Sep 2008 - present Professor, Department of Applied Physics, The Hong Kong Polytechnic University April 2007 – Aug 2008 Assistant Head, Division of Microelectronics, School of Electrical and Electronic Engineering, Nanyang Technological University Jan. 2004 - Aug 2008 Associate Professor, School of Electrical and Electronic Engineering, Nanyang Technological University Oct. 1998 – Dec. 2003 Assistant Professor, School of Electrical and Electronic Engineering, Nanyang Technological University Feb. 1996- Oct. 1998 Research Fellow, Department of Electronic Engineering, University of Surrey, U.K. Fe. 1995 – Jan. 199 Senior Research Assistant, Department of Materials Engineering, University of Wales Swansea, U.K. Oct. 1991 – Feb. 1995 Research Student, Department of Materials Engineering, University of Wales Swansea, U.K. |
| Location |
PH L1 503 (The aquarium )
|
| Category | Conferences - Seminars |
Strain engineering is a powerful and widely used strategy for boosting the performance of electronic, optoelectronic and spintronic devices. By applying a strain through lattice mismatch between epitaxial films and substrates or through bending of films on elastic substrates, this strategy can be used to increase the carrier mobility in semiconductors or to lift the emission efficiency of light-emitting devices. Particularly, due to reduced dimensions, nanostructures become more flexible to be highly strained, which provides more space for strain engineering. Although low-dimensional nanostructures are relatively flexible, the reported tunability of bandgap is within 100 meV per 1% strain. It is also challenging to control strains in atomically thin semiconductors precisely and monitor the optical and phonon properties simultaneously. We developed an electro-mechanical device that can apply biaxial compressive strain to chemical vapor deposited MoS2 nanosheets supported by a piezoelectric substrate and covered by a transparent graphene electrode. Photoluminescence and Raman characterizations show that the direct bandgap can be blue-shifted for ~300 meV per 1% strain. The exceptional high strain tunability of electronic structure in MoS2 promising a wide range of applications in functional nanodevices and the developed methodology should be generally applicable for two-dimensional semiconductors.
Host: Oleg Yazyev and Laszlo Forro
Host: Oleg Yazyev and Laszlo Forro
Links
Practical information
- Informed public
- Free
Organizer
- ICMP (Arnaud Magrez and Raphaël Butté)
Contact
- Arnaud Magrez ([email protected])