Colloidal quantum dots for mid-IR applications

Abstract

The use of colloidal material offers an interesting alternative to top down approaches for the realization of low cost infrared detectors. We demonstrate photoconduction in thin films of a colloidal material in the mid infrared (up to 7µm), using HgTe colloidal quantum dots. Thin films of the colloidal quantum dots have a large absorption coefficient (>10 4 cm-1), and the photoconductive response is dramatically improved by encapsulating the nanoparticle into an inorganic matrix of As2S3. Such devices show fast response and large detectivity (>10 10 jones) at temperatures above 200 K.

In2S3 Quantum Dots: Preparation, Properties and Optoelectronic Application

“…2a, is very close to the calculated value using the Brus equation ( E np =3.50 eV). Photoluminescence (PL) and photoluminescence excitation (PLE) [21] studies were performed to investigate the optical properties of the In 2 S 3 QDs. It can be seen from Fig.…”

Advances of Sensitive Infrared Detectors with HgTe Colloidal Quantum Dots

“…Over the past decade, CQDs have been widely used in a variety of applications, including solar cells [24], spectrometers [25], phototransistors [26], FPA imagers [27], lasers [28], LEDs [29]. Among all the CQDs systems, mercury telluride (HgTe) CQDs have demonstrated the highest infrared spectral absorption tunability covering main important atmospheric windows including short-wave infrared (SWIR, 1.5-2.5 µm) [30][31][32][33], mid-wave infrared (MWIR, 3-5 µm) [34][35][36][37][38][39][40][41][42], long-wave infrared (LWIR, 8-12 µm) [43,44] and even the terahertz (THz) [45,46], appearing as promising candidates to substitute conventional semiconductors to achieve good detection performance with low cost. This review will be described from the following aspects, including: synthesis of infrared CQDs, infrared CQDs photodetectors, multispectral CQDs photodetectors and CQDs FPA.…”

Colloidal quantum dots for thermal infrared sensing and imaging

“…Lhullier et al [24–26] took the newly improved synthesis and further studied the charge carrier transport properties and optical properties after employing a ligand exchange procedure with ethanedithiol (EDT). Around the same time, Kovalenko et al demonstrated that As 2 S 3 can be used as an infrared transparent ligand for PbS and CdS particles [27] which led to new ligand exchange and inorganic matrix studies [28, 29]. The synthesis protocol used for these experimental works closely followed the monodisperse synthesis in late 2011 but instead of oleylamine, octadecylamine (ODA) was used.…”