Germanium (Ge) is a grey-white semimetal element that is commonly used in fiber optic cables. It is a useful material for high-frequency electrical conductivity and is known for its low-light sensitivity. Germanium is often used as a detector in fiber optics due to its ability to detect light in the range of 800-1600 nm wavelengths, which is the frequency range of most fiber optic cables.

Germanium is preferred over other materials, such as indium gallium arsenide (InGaAs), because of its lower cost and better performance. InGaAs detectors can be more sensitive to light, but they are much more expensive. Germanium is also very useful in high-speed cable applications, as it has a higher dielectric constant than other materials.

Germanium is often used in the construction of fiber optic cables due to its low-light sensitivity and ability to transmit high-frequency signals. It is used in both single-mode and multimode fiber cables, as it is able to carry a greater range of wavelengths. Germanium is also used in cable connectors, as it is more resistant to corrosion and electrical interference than other materials.

Germanium is an essential component in the development of fiber optic cables, as it allows for the transmission of light through the cables. It is a cost-effective material that provides excellent performance, making it an ideal choice for many cable applications. Germanium has been used in the development of fiber optic cables for decades, and it is likely to remain an important component of the industry for many years to come.