New Chip-Based Amplifier Revolutionizes Fiber-Optic Communication

In a recent study published in Nature, researchers from Chalmers University of Technology in Sweden introduced a new amplifier that enables a data rate ten times higher than what is currently achievable with fiber-optic systems. This amplifier, which can be integrated into a small chip, holds potential for a variety of important laser systems, including those used in medical diagnosis and treatment.

Data traffic is expected to double by 2030, driven by factors such as the advancement of AI technology, the growing popularity of streaming services, and the proliferation of new smart devices. This increase in data usage is raising the demand for communication systems capable of handling large volumes of data.

Currently, telecommunications, the Internet, and other data-intensive services rely on optical communication systems. These systems use light to transmit information over long distances. Laser pulses travel through thin glass strands in optical fibers at high speeds, enabling data transmission.

Optical amplifiers play a critical role in preserving data quality by preventing signals from being overwhelmed by noise. The amplifier's bandwidth, or the range of light wavelengths it can process, is a key determinant of the data transmission capacity in an optical communication system.

The amplifiers currently used in optical communication systems have a bandwidth of approximately 30 nm. Our amplifier, however, boasts a bandwidth of 300 nm, enabling it to transmit ten times more data per second than those of existing systems.

Peter Andrekson, Professor and Study Lead Author, Photonics, Chalmers University of Technology

Small, Sensitive, and Powerful

The new amplifier uses several small, spiral-shaped, interconnected waveguides in silicon nitride to direct light with minimal loss. The combination of this material with an optimized geometric design has resulted in several technical advantages.

The key innovation of this amplifier is its ability to increase bandwidth tenfold while reducing noise more effectively than any other type of amplifier. This capability allows it to amplify very weak signals, such as those used in space communication.

Peter Andrekson, Professor and Study Lead Author, Photonics, Chalmers University of Technology

Additionally, the system has been successfully miniaturized by the researchers to fit onto a chip just a few centimeters in size.

“While building amplifiers on small chips is not a new concept, this is the first instance of achieving such a large bandwidth,” added Peter Andrekson.

Contributes to Earlier Detection of Diseases

The researchers have integrated multiple amplifiers onto the chip, making the design easily scalable. This configuration allows for the creation of laser systems capable of quickly adjusting wavelengths over a broad range. As optical amplifiers are critical components in all lasers, this invention has numerous potential applications.

Minor adjustments to the design would enable the amplification of visible and infrared light as well. This means the amplifier could be utilized in laser systems for medical diagnostics, analysis, and treatment. A large bandwidth allows for more precise analyses and imaging of tissues and organs, facilitating earlier detection of diseases.

Peter Andrekson, Professor and Study Lead Author, Photonics, Chalmers University of Technology

In addition to its versatility, the amplifier can help reduce the size and cost of laser systems.

“This amplifier offers a scalable solution for lasers, enabling them to operate at various wavelengths while being more cost-effective, compact, and energy-efficient. Consequently, a single laser system based on this amplifier could be utilized across multiple fields. Beyond medical research, diagnostics, and treatment, it could also be applied in imaging, holography, spectroscopy, microscopy, and material and component characterization at entirely different wavelengths,” explained Peter Andrekson.

Further Insights into the Amplifier's Potential

The researchers demonstrated that the amplifier operates effectively within the 1400–1700 nm range of the optical communication spectrum. Due to its broad 300 nm bandwidth, the amplifier can be adjusted for use at other wavelengths.

By modifying the waveguide design, signals in other ranges, such as visible light (400–700 nm) and infrared light (2000–4000 nm), can also be amplified. This flexibility opens the possibility for the amplifier's use in applications such as disease diagnosis, treatment, internal organ and tissue visualization, and surgery, where visible or infrared light is essential.

Journal Reference:

Zhao, P., et al. (2025) Ultra-broadband optical amplification using nonlinear integrated waveguides. Nature. doi.org/10.1038/s41586-025-08824-3.