Researchers at the Technical University of Denmark have developed a new energy-efficient fiber optic cable that boasts an impressive transmission rate of 661 TBit/s. While fiber optic cables have many advantages over traditional copper cables, they require a significant amount of energy to operate. In fact, approximately nine percent of the world’s energy resources are used to power the internet, of which fiber optic cables are an integral part. To address this issue, Hao Hu and his team combined various established techniques, such as time-division multiplexing and wavelength-division multiplexing, to create a fiber optic cable that requires only a fraction of the energy and achieves a transmission rate of 661 TBit/s.
The researchers used multiple lasers to cover as many color spaces of light as possible, with a 300-nanometer-thick wire amplifying the light sources and helping to break the light into further spectra. The resulting pulsating lasers created a mixture of different colors within the fiber optic cable, which ultimately resulted in a single color. Additionally, the researchers utilized two different polarizations of the electromagnetic fields within the cable to further increase the data rate. The transmitted data is divided into four time intervals, made possible by the laser’s pulsing, resulting in a data transmission rate of 25 TBit/s per fiber. The researchers reported in the journal Nature that theoretically, 750 TBit/s would be possible with 30 fibers, but redundancies in the signal coding reduce the final transmission rate to 661 TBit/s.
Compared to traditional single-mode and multi-mode fiber optic cables, the new cable has a thinner core and thicker cladding, resulting in a more energy-efficient design. While the new cable’s transmission rate is impressive, it is still in the research phase and not yet commercially available. However, it has the potential to revolutionize the internet’s energy consumption and data transmission capabilities.
