Coherent Announces Industry’s First L-Band 800G ZR/ZR+ Pluggable Transceivers

Image 1: 800G QSFP-DD coherent pluggable transceiver.

PITTSBURGH, Sept. 17, 2024 (GLOBE NEWSWIRE) -- Coherent Corp. (NYSE: COHR), a leader in high-speed optical networking technology, today announced the industry’s first L-band 800 Gbps coherent pluggable transceiver in a QSFP-DD form factor. This innovative product will be showcased at in Frankfurt, Germany, Sept. 23-25, 2024.

Hyperscale data centers and telecom carriers require solutions to expand fiber capacity at lower costs. By expanding from C-band to L-band, fiber capacity can double from 32 Tbps to 64 Tbps. Historically, L-band has been supported with proprietary systems from network equipment manufacturers. The new standardized 800G ZR/ZR+ pluggable module from Coherent now allows disaggregation, supporting an open ecosystem in a smaller and more efficient form factor.

“Building on the success of the world’s first C-band 140 GBaud IC-TROSA, Coherent has successfully extended the technology to the L-band with our new pluggable module,” said Dr. Beck Mason, Executive Vice President, Telecommunications. “We now feature both C-band and L-band 800G coherent transceivers with high optical output power, which delivers best-in-class transmission performance. We continue to advance the state of the art of optical transmission in core networks by leveraging the inherent capabilities of our indium phosphide technology platform to benefit our end customers.”

“With the ever-growing bandwidth demands of DCI and telecom networks, L-band transmission has become essential,” said Kyle Hollasch, Lead Analyst for Transport Hardware at Cignal AI. “L-band ROADM shipments have nearly doubled over the past 12 months, and hyperscale DCI requirements are poised to grow the market for L-band pluggable coherent transceivers even more rapidly.” 

With the availability of L-band 800G ZR/ZR+ transceivers in both QSFP-DD and OSFP form factors, Coherent enhances the capacity and performance coverage of IP-over-DWDM (dense wavelength division multiplexing) applications. These modules enable coherent interfaces directly on routers and switches, eliminating the need for additional optical equipment, thus reducing costs by more than 400%.

The 800G ZR/ZR+ transceiver leverages the Coherent L-band 140 Gbaud IC-TROSA-integrated coherent optical subassembly, which features a high-efficiency, internally designed and manufactured indium phosphide modulator and receiver combined with an embedded wavelength-tunable laser. This delivers compelling cost, power, size, and performance advantages compared with L-band implementations based on silicon photonics, which need micro-EDFAs, adding cost and power dissipation and consuming precious real estate in compact form factors such as QSFP-DD.



“Driven by emerging data-hungry applications, the rapid adoptions of Generative AI solutions, and ubiquitous video consumption from any place and device, we marvel at the relentless trajectory of bandwidth consumption,” said AE Natarajan, Executive Vice President, Chief Development Officer, Juniper Networks. “Adding L-band 800 ZR/ZR+ pluggable solutions to the toolbox, effectively doubling the capacity of existing fiber plants, is invaluable and reassuring to network operators. Fortunately, many operators had the foresight to deploy L-band-ready line systems, anticipating the future need to scale network capacity rapidly. By leveraging the QSFP-DD form factor, Coherent enables vendors like Juniper to deliver highly flexible and scalable IPoDWDM solutions that facilitate port-by-port configuration of 800G direct-detect and/or coherent optics, and now C-band or L-band DWDM optics, mitigating bottlenecks in a myriad of cloud and telecom use cases.”

Coherent will demonstrate the 800G L-band transceiver module in a PTX10002-36QDD Juniper router at ECOC 2024, showcasing the transceiver’s capabilities in an IP-over-DWDM configuration. The module is designed for various line modulation formats and supports 800 Gbps extended-reach, 600 Gbps, and 400 Gbps long-reach applications.

Customer sampling will begin in the fourth quarter of 2024.

About Coherent

Coherent empowers market innovators to define the future through breakthrough technologies, from materials to systems. We deliver innovations that resonate with our customers in diversified applications for the industrial, communications, electronics, and instrumentation markets. Headquartered in Saxonburg, Pennsylvania, Coherent has research and development, manufacturing, sales, service, and distribution facilities worldwide. For more information, please visit us at .

Media Contact:

Amy Wilson

Manager, Corporate Communications & Investor Relations

A photo accompanying this announcement is available at