Optically induced trion formation and its control in a MoS/graphene van der Waals heterostructure.

Monolayer 2D transition metal dichalcogenides (TMDs) show high sensitivity to the local dielectric environment, leading to modulation of their optoelectronic properties. Here, we report on the formation of localized trions in a MoS/few-layer graphene van der Waals heterostructure. We performed temperature-dependent photoluminescence and Raman studies down to 80 K, to understand the mechanism for localized charge excitation, which shows contrasting behaviour with MoS/SiO.

Strain relaxation in monolayer MoS over flexible substrate.

In this communication, we demonstrate uniaxial strain relaxation in monolayer (1L) MoS transpires through cracks in both single and double-grain flakes. Chemical vapour deposition (CVD) grown 1L MoS has been transferred onto polyethylene terephthalate (PET) and poly(dimethylsiloxane) (PDMS) substrates for low (∼1%) and high (1-6%) strain measurements. Both Raman and photoluminescence (PL) spectroscopy revealed strain relaxation cracks in the strain regime of 4-6%.

Quantum emitters and detectors based on 2D van der Waals materials.

Light plays an essential role in our world, with several technologies relying on it. Photons will also play an important role in the emerging quantum technologies, which are primed to have a transformative effect on our society. The development of single-photon sources and ultra-sensitive photon detectors is crucial.