Localized strain tuning of exciton emissions on suspended two-dimensional materials*

Two-dimensional materials can endure extraordinarily large strain which strongly influences its electronic and optical properties¹. Strain tuning has been reported for free excitons in transition metal dichalcogenides (TMDs) ^2,3 as well as for single photon emissions in TMDs⁴ or in hexagonal boron nitrides (hBN)⁵. However, strain applied on the entire substrate or over few micrometers has a limited ability to produce or control individual strain-induced quantum emissions in TMDs. Here we demonstrate extremely localized strain tuning of exciton emissions in suspended 2D materials induced by sub-10nm radius tip mechanical probe, which can be potentially used to create and tune nonclassical light sources in atomically thin materials.

1. Johari and Shenoy, ACS Nano 6 (6), pp 5449–5456 (2012)
2. Zhu et al., Physical Reviews B 88, 121301 (2013)
3. Llyod et al., Nano Letters 16 (9), pp 5836–5841 (2016)
4. Chakraborty et al., in preperation
5. Grosso et al., Nature Communications 8, 705 (2017)