Tunable and Reconfigurable Atomically Thin Heterostructures

INV-17004

 

This invention shows that crystallographically dissimilar and incommensurate atomically-thin MoS₂ and Bi₂Se₃ layers can form rotationally-aligned stacks with long-range crystallographic order. Our theory predicts and experiments reveal striking electronic and optical changes when Bi₂Se₃ is stacked layer-by-layer on monolayer MoS₂, including the formation of an indirect bandgap and 100% photoluminescence (PL) suppression, tunable transmittance-edge (1.1 eV®0.75 eV), suppressed Raman, and wide-band evolution of spectral transmittance. The range of edge energies is highly attractive for beyond-silicon electronics and optoelectronics, especially for telecommunications wavelengths that require active electronics at the 1550 nm (0.8 eV) standard.

Tunable absorbance, reflectance, and photoemission in these crystals make them potentially important for various photovoltaic and photodetection applications in the visible range. Disrupting the rotational alignment using a focused laser results in a spectacular reversal of PL, Raman, and transmittance, demonstrating for the first time that in-situ manipulation of interfaces can enable “reconfigurable” 2D materials. Northeastern University researchers have utilized this laser-writing approach to demonstrate 2D heterocrystals with patterns, arrays, and optical information (bit) storage abilities. It is possible to conceive various photonic, plasmonic and optoelectronic applications that may benefit from such highly precise optical arrays and circuit-drawing in an atomically-thin material.

 

Northeastern University researchers present a new type of vertical stacking between 2D crystals of molybdenum disulfide (MoS₂) tri-layers (TLs) and bismuth selenide (Bi₂Se₃) quintuple layers (QLs). This includes a process for the controlled synthesis of a uniquely new class of vertically stacked 2D heterocrystals with a novel “switchable” PL, and widely-tunable optical transmittance values and transmittance edges. The range of edge energies is highly attractive for beyond-silicon electronics and optoelectronics, especially for telecommunications wavelengths that require active electronics at the 1550 nm (0.8 eV) standard. Tunable absorbance, reflectance, and photoemission in these crystals make them potentially important for various photovoltaic and photodetection applications in the visible range.

Also presented a novel laser-induced reversal of the electronic and optical properties, especially the striking manner in which the PL can be reversed, and its sharp vs. broadband nature can be tuned.

Atomically thin materials are stack-able with a particular alignment.

 

- Atomically thin materials (< 10 nm)

- Reconfigurable by laser with sub-micron resolution

- Synthesized by chemical vapor deposition (CVD)

 

- Optical communication

- Opto-Electronic applications like flexible electronics

- Light-emitting

- Optical sensing

 

- License

- Partnering

- Research collaboration