Widely tunable Bi 2 Se 3 /transition metal dichalcogenide 2D heterostructures for write-read-erase-reuse applications

We present a method to tune the photoluminescence (PL) and exciton dynamics in a family of 2D heterostructures by controllably disrupting the interlayer coupling. Growing 1–3 layers of Bi 2 Se 3 on arbitrary monolayer transition metal dichalcogenides (TMDs), including alloys, quenches the TMDs signature PL. Applying controlled doses of energy in air modulates the PL upward in small increments, while thermal annealing in Ar or N 2 reverses those changes. This PL-tuning can even be accomplished locally using a low-power laser, allowing complex patterns with submicron features to written. We demonstrate this over a wide-range of emission energy values in the visible (1.5 eV < E ph < 2 eV), suggesting this family of 2D materials is well-suited for applications requiring ‘write-read-erase-reuse’ capability.