Narrow-band photodetection by heterolattice electronic transitions in TiO$_2$ glass embedded with nanocrystals

TL;DR

This paper demonstrates narrow-band photodetection in TiO2 glass films with embedded nanocrystals, utilizing heterolattice electronic transitions to achieve high spectral selectivity for potential nanoscale applications.

Contribution

It introduces a novel NanoHLET mechanism for narrow-band photodetection in TiO2 glasses with embedded nanocrystals, enabling ultra-small, highly selective photodetectors.

Findings

Sharp responsivity peak at 423.0 nm with 13.7 nm FWHM

Narrowband detection achieved via heterolattice electronic transitions

Potential for nanoscale photodetector development

Abstract

In this letter, we propose that the narrowband photodetection can be realized in the skin layer of semiconductors with the spatially separated photo-excited carriers from the nanoscale heterolattice electronic transitions (NanoHLETs). The NanoHLET photodetection is demonstrated by measuring the photoconductive responses of the $\sim$ 1 $\mu$m thick films of TiO$_{2}$ glass embedded with rutile and anatase TiO$_{2}$ nanocrystals. As containing only rutile nanocrystals, the TiO$_{2}$ glass film presents the responsivity curve with only one sharp peak centered at 423.0 nm with a full-width-at-half-maximum (FWHM) of 13.7 nm. This NanoHLET mechanism may open a new way in making ultra-small narrow-band photodetectors matching the current nanoscale electronic technology.