Advanced Methods of Semiconductor Research Seminar – Tuesday 29th of April 2025
We cordially invite you to Advanced Methods of Semiconductor Research Seminar on Tuesday 29th of April 2025 at 13:15 in room 321, building A-1, where there will be delivered a lecture:
Strain Engineering of TMDs Monolayers on GaAs Nanomembranes
by Ewelina Cybula
from Department of Experimental Physics, Wrocław Tech
Lecture abstract:
Transition metal dichalcogenides (TMDs) possess an excellent mechanical robustness and flexibility, which enable them to withstand strains as high as 10% before reaching the fracture point. Therefore, strain engineering has become a particularly attractive tool to tailor their electronic and vibrational properties or to preferentially funnel photoexcited carriers towards defects, which act as single photon emitters [1]. One of the approaches to site-control these quantum light emitters is the deposition of TMD monolayers on patterned substrates [1], thereby imposing spatially controlled strain on the two-dimensional layers.
So far, patterned substrates consist mainly of SiO2 nanostructures, which, however, suffer from surface charge instability. Here, we explore an alternative approach to deterministically imposing strain on TMD layers by making use of high-quality, epitaxially grown III-V semiconductor nanostructures.
We show a successful deposition of MoSe2 , WSe2, WS2 monolayer on GaAs nanomembranes. By performing photoluminescence, reflectance and Raman spectroscopy and mapping technique, we show that the TMD monolayer deposited on GaAs nanomembranes was effectively strained.
[1] Branny, A., Kumar, S., Proux, R. et al., Nat Commun 8, 15053 (2017).
