Chemical defects that fluoresce in the shortwave infrared open exciting opportunities in deep-penetration bioimaging, chemically specific sensing, and quantum technologies. However, the atomic size of defects and the high noise of infrared detectors have posed significant challenges to the studies of these unique emitters. Here we demonstrate high throughput single-defect spectroscopy in the shortwave infrared capable of quantitatively and spectrally resolving chemical defects at the single defect level. By cooling an InGaAs detector array down to −190 °C and implementing a nondestructive readout scheme, we are able to capture low light fluorescent events in the shortwave infrared with a signal-to-noise ratio improved by more than three orders-of-magnitude. As a demonstration, we show it is possible to resolve individual chemical defects in carbon nanotube semiconductors, simultaneously collecting a full spectrum for each defect within the entire field of view at the single defect limit.
Organic color‐centers (OCCs) have emerged as promising single‐photon emitters for solid‐state quantum technologies, chemically specific sensing, and near‐infrared bioimaging. However, these quantum light sources are currently synthesized in bulk solution, lacking the spatial control required for on‐chip integration. The ability to pattern OCCs on solid substrates with high spatial precision and molecularly defined structure is essential to interface electronics and advance their quantum applications. Herein, a lithographic generation of OCCs on solid‐state semiconducting single‐walled carbon nanotube films at spatially defined locations is presented. By using light‐driven diazoether chemistry, it is possible to directly pattern
- Publication Date:
- NSF-PAR ID:
- Journal Name:
- Advanced Materials
- Wiley Blackwell (John Wiley & Sons)
- Sponsoring Org:
- National Science Foundation
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