Colloidal quantum dots for infrared detection beyond silicon

Abstract

This perspective describes the advantages of infrared colloidal quantum dots (CQDs) for photodetection beyond silicon and provides a brief review of the development of CQD photodetection. The standard specifications for photodetectors are listed with particular emphasis on the detectivity. High gain improves the responsivity but does not improve the detectivity, while nonradiative losses do not prevent high responsivity but limit the detectivity. Performances of CQD detectors and HgTe CQDs, in particular, are compared with the maximum possible detectivity based on detailed balance from the device temperature and nonradiative losses.

Functional materials and devices by self-assembly

“…Epitaxial quantum dots are used as efficient single-photon emitters for quantum information technologies, 67 colloidal nanocrystals are employed in light-emitting devices, 68 including flat panel displays and infrared sensors. 69,70 Block copolymers are being extensively tested by leading microelectronics companies and have been included in the International Roadmap for Devices and Systems. 71 However, extreme ultraviolet (EUV) lithography and other developments in this fast-moving semiconductor industry poses high activation barriers for radically new technologies.…”

Designing an Ultrathin Film Spectrometer Based on III-Nitride Light-Absorbing Nanostructures

“…Collimation optics typically consist of a narrow aperture, either a slit or pinhole, and a lens, adding to the system bulkiness and weight. A spectrometer design based on absorptive spectral parsing elements was recently proposed and demonstrated using both colloidal quantum dots and epitaxial nanostructures [4,[13][14][15][16][17]. Because light absorption in nanostructures only weakly depends on the incident angle [18,19], an absorption-based spectrometer can enable a much more flexible and compact optical design, which benefits the realization of a spectrometer array for hyperspectral imaging or sensors with multiple modalities.…”

Tin(IV) Methylselenolate as a Low Temperature SnSe Precursor and Conductive “Glue” Between Colloidal Nanocrystals

“…PbSe nanocrystals have been explored for a wide variety of electronic applications including transistors, photodetectors, and solar cells . In pursuit of these applications, a wide variety of post‐synthesis chemical and/or thermal treatments have been explored to improve charge transport properties.…”

“…Colloidal semiconductor nanocrystals are an attractive and fast‐developing class of materials that find use in electronic, optoelectronic, and thermoelectric applications . Moreover, they recently achieved commercial implementation for television displays, and are being actively investigated for photodetectors, solar cells, and transistors . Colloidal nanocrystals are particularly useful because of their synthesis scalability and their solution processability that enables cost reductions ( e. g ., inkjet printing, spray coating, spin coating, etc .).…”