Giant gate-tunable bandgap renormalization and excitonic effects in a 2D semiconductor.

Understanding the remarkable excitonic effects and controlling the exciton binding energies in two-dimensional (2D) semiconductors are crucial in unlocking their full potential for use in future photonic and optoelectronic devices. Here, we demonstrate large excitonic effects and gate-tunable exciton binding energies in single-layer rhenium diselenide (ReSe) on a back-gated graphene device. We used scanning tunneling spectroscopy and differential reflectance spectroscopy to measure the quasiparticle electronic and optical bandgap of single-layer ReSe, respectively, yielding a large exciton binding energy of 520 meV.

Tailoring sample-wide pseudo-magnetic fields on a graphene-black phosphorus heterostructure.

Spatially tailored pseudo-magnetic fields (PMFs) can give rise to pseudo-Landau levels and the valley Hall effect in graphene. At an experimental level, it is highly challenging to create the specific strain texture that can generate PMFs over large areas. Here, we report that superposing graphene on multilayer black phosphorus creates shear-strained superlattices that generate a PMF over an entire graphene-black phosphorus heterostructure with edge size of tens of micrometres.

Dynamic band-structure tuning of graphene moiré superlattices with pressure.

Heterostructures can be assembled from atomically thin materials by combining a wide range of available van der Waals crystals, providing exciting possibilities for designer electronics . In many cases, beyond simply realizing new material combinations, interlayer interactions lead to emergent electronic properties that are fundamentally distinct from those of the constituent layers . A critical parameter in these structures is the interlayer coupling strength, but this is often not easy to determine and is typically considered to be a fixed property of the system.

The use of orientation/decision/do/discuss/reflect (OD3R) method to increase critical thinking skill and practical skill in biochemistry learning.

We have developed an OD3R method that can be applied on Biochemistry learning. This OD3R consists of 5 phases: orientation, decision, do, discuss, and reflect to connect lessons in the class with practice in the laboratory. Implementation of OD3R method was done in 2 universities in Yogyakarta to increase critical thinking skill and practical skill of the students.