Coherent Demonstrates Industry’s First 400G Differential Electro-Absorption Modulated Laser

SAXONBURG, Pa., March 27, 2025 (GLOBE NEWSWIRE) -- Coherent Corp. (NYSE: COHR), a global leader in photonics, is demonstrating the industry's first 400 Gb/s Differential Electro-absorption Modulated Laser (D-EML) at OFC 2025. This represents a significant advance in high-speed optical networking technology for data centers. 

Built on the success of its 200G D-EML, which was recognized in the 2025 Lightwave+BTR Innovation Reviews, this innovative D-EML by Coherent addresses critical challenges in optical transceiver designs for 1.6T and future 3.2T connectivity driven by explosive AI infrastructure growth. Unlike traditional single-ended EMLs, its differential design effectively doubles the signal amplitude, significantly lowering overall power consumption while minimizing crosstalk.   This enables the differential EML to deliver superior OMA and ER performance.   An integrated on-chip termination network further optimizes electrical performance, reducing the need for extensive signal pre-conditioning and enhancing signal integrity. The D-EML builds upon proven EML technology from Coherent and is designed for use in low-cost, non-hermetic packaging solutions. 

"This pioneering differential EML design underscores our commitment to innovation and technology leadership," said Dr. Beck Mason, Executive Vice President, Telecommunications at Coherent. "Leveraging our vertical integration capabilities, we continue to empower the data center market’s evolution. We also take this opportunity to thank Ciena for their support in providing a DSP chip to drive this laser for the demonstration.”  

The 400G D-EML will be demonstrated at OFC 2025 and supplied under controlled availability upon request, while the 200G D-EML general availability is expected in 2026. Visit booth #1519 at OFC 2025 in San Francisco, April 1-3 to see innovative demonstrations and learn more about the extensive portfolio of optical and semiconductor high-performance solutions from Coherent. 

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. Coherent has research and development, manufacturing, sales, service, and distribution facilities worldwide. For more information, please visit us at .  

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