# Peking University develops unified silicon photonic coherent link for all distances

- Published: 2026-11-06 15:31 UTC
- Section: Machines & Making › Electronics
- Tags: silicon photonics coherent solution, all-distance optical communications, Peking University photonics, Nature Communications optical link, silicon nitride external cavity laser
- URL: https://realtech.media/news/rt-44f8f640c318af1ec432674e_peking_university_develops/

**Researchers presented a coherent silicon photonic architecture operating without optical amplification over short links and reaching over 4,400 km.**

![Peking University develops unified silicon photonic coherent link for all distances](https://sgzwpqqelzmajkcubgkl.supabase.co/storage/v1/object/public/rt-media/2026/11/82af21b2da15fc41.jpg)
*UC Davis College of Engineering, Wikimedia Commons, CC BY 2.0*

Researchers from Peking University, SiFotonics Technologies, and the Chinese Academy of Sciences have demonstrated a unified silicon photonic coherent platform designed for all-distance optical communications, according to a study published in Nature Communications [1]. The architecture addresses the traditional division between short-reach links, which typically rely on intensity modulation due to hardware and energy constraints, and long-haul systems that require coherent transmission for high capacity.

## Laser specifications and integrated transceiver

The platform utilizes a laser integrated with an ultralow-loss silicon nitride external cavity [1]. This configuration achieves a direct optical output power of 70 mW, a sub-kilohertz spectral linewidth, and a wall-plug efficiency of 13.7% [1]. Paired with silicon photonic transceivers, the system provides high spectral efficiency while mitigating the hardware complexity that previously restricted coherent optical architectures to long-distance infrastructures [1].

## Short-reach throughput and long-haul transmission

During experimental evaluations, the platform supported unamplified short-distance data transmission across 256 wavelength channels, reaching an aggregate data rate of 81.92 Tb/s [1]. For long-distance communications, the coherent platform maintained transmission over distances exceeding 4,400 km [1]. Furthermore, the system demonstrated wavelength switching and the re-establishment of data transmission on timescales of tens of microseconds, enabling dynamic wavelength-routed optical connectivity [1].

## Sources

1. [Nature Communications](https://doi.org/10.1038/s41467-026-79026-2)

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Source: RealTech, realtech.media — https://realtech.media/news/rt-44f8f640c318af1ec432674e_peking_university_develops/