Advanced Optical Materials

Broadband high-responsivity photodetectors are fabricated by a simple molecular beam epitaxy process from SnTe ultrathin films. The photoconductive detectors exhibit a fast and stable photoresponse from the visible to the mid-infrared range (405 nm–3.8 µm) with a relatively high responsivity (3.75 AW⁻¹ at 2003 nm and room temperature), which will promote the applications of broadband and sensitive optoelectronic devices.

Boron nitride quantum dots (BNQDs) with solvent-regulated blue/green photoluminescence and electrochemiluminescent behavior are prepared using liquid exfoliation–solvothermal treatment of bulk BN. The sizes, quantum yields, and optical properties of the BNQDs are varied with different polarity of the tested solvents. Different kinds of BNQDs can be chosen on-demand for applications in label-free specific ferric ion detection, cell imaging, and fiber staining.

A new approach to fabricate speckle image holography metasurfaces with chaotic carrier fringes for broadband photon management is demonstrated. Using this holography metasurfaces structure allows to sculpt wavefronts of light almost at will.

A new type of multifunctional barrier film is proposed that prevents penetration by both water and ultraviolet (UV) light. To enable a low-cost and simple process, a fabrication approach is developed that uses UV-distributed Bragg reflector structures to combine thin-film passivation and a UV reflector.