Key Findings
The study reports a high-efficiency, heavy-metal-free SWIR LED operating at 1525 nm. The device achieves a maximum external quantum efficiency (EQE) of 3.5% and a record radiance of ~17 W sr⁻¹ m⁻², with a T50 operational lifetime of 16 h. A critical breakthrough is the achievement of PLQYs exceeding 55% for emission beyond 1400 nm, surpassing previous limits where emission in this range typically yielded PLQY below 20%.
Technical Details
The performance gains are attributed to two primary strategies:
- Shell Growth Control: The use of optimized high-temperature ZnCl₂ treatment and continuous precursor injection improved shell nucleation and growth.
- Interfacial Engineering: Controlled interfacial oxidation reduced shell-thickness-dependent strain signatures and improved PLQY retention during the thickening of the shell.
To optimize the device architecture, a semiconducting InAs CQD interlayer was incorporated to suppress interfacial quenching and regulate electron over-injection. Additionally, a doped hole-transport layer was used to reduce series resistance.
Background & Context
SWIR light sources are essential for optical communication, deep-tissue bio-imaging, and machine vision. While conventional epitaxial SWIR LEDs exist, they face high manufacturing costs and strict lattice-matching requirements. Colloidal quantum dots (CQDs) offer a cost-effective, solution-processable alternative. InAs CQDs are promising lead-free candidates, but achieving high PLQY beyond 1400 nm has been hindered by surface defects and interfacial strain. Previous InAs-based CQD LEDs beyond 1.4 μm had reached an EQE of 1.1% at 1410 nm.
Significance & Outlook
By integrating mechanism-driven shell growth with rational device engineering, this approach overcomes current bottlenecks in colloidal emitters. The transition to heavy-metal-free, RoHS-compliant materials like InAs/ZnSe facilitates the scalable integration of SWIR emitters into silicon-based technologies and other short-wave infrared applications.
Source: https://doi.org/10.1038/s41467-026-77896-0
Get our weekly technology intelligence — free
Receive an infographic that lets you judge at a glance whether each field’s analysis report is worth reading.
Subscribe Free — Weekly Tech Intelligence
By subscribing, you’ll receive Troy-Technical’s weekly technology intelligence newsletter.
- Your email and selected fields are used only to deliver the newsletter.
- We never share your information with third parties.
- You can unsubscribe anytime via the link in each email.
See our Privacy Policy for details.
Takes about a minute · Unsubscribe anytime
