September 2023

Researchers use perovskites and 2D TMDs to create a promising valleytronics material

Researchers from the US DOE Brookhaven National Laboratory, together with Northrop Grumman, have found a way to maintain valley polarization at room temperature using novel materials and techniques. 

The researchers used a chiral lead halide perovskite material (R/S-NEAPbI3). The researchers layered 500 nanometer thick flakes onto a monolayer molybdenum disulfide (MoS2), to create what is known as a heterostructure. Using a linearly polarized laser to excite the heterostructure the researchers fabricated and then measured the light that was emitted from the molybdenum disulfide TMD using a confocal microscope. They have discovered that the new material is promising for valletronics applications.

Read the full story Posted: Sep 10,2023

Researchers show that Platinum diselenide is a promising 2D material for terahertz valleytronics

Researchers from CNRS in France demonstrated that Platinum diselenide (PtSe2) is a promising 2D material for a terahertz (THz) range valleytronics device.

The researchers explain that PtSe2 is promising as, unlike other transition metal dichalcogenides (TMDs), its bandgap can be uniquely tuned from a semiconductor in the near-infrared to a semimetal with the number of atomic layers. This gives the material unique THz photonic properties that can be layer-engineered. In this research, the main demonstration was that a controlled THz nonlinearity - tuned from monolayer to bulk - can be realized in wafer size polycrystalline through the generation of ultrafast photocurrents and the engineering of the bandstructure valleys. 

Read the full story Posted: Sep 07,2023