Germanium America, 30–50% of current fiber optic lines are unused dark fiber, sparking discussion of over-production and a future reduction in demand. Worldwide, demand is increasing dramatically as countries such as China are installing fiber optic telecommunication lines throughout the country. Germanium Germanium is a chemical element with symbol Ge and atomic number 32. It is a lustrous, hard, grayish-white metalloid in the carbon group, chemically similar to its group neighbors tin and silicon. Pure germanium is a semiconductor with an appearance similar to elemental silicon. Like silicon, germanium naturally reacts and forms complexes with oxygen in nature. Because it seldom
Antimony telluride Antimony telluride Antimony telluride is an inorganic compound with the chemical formula SbTe. It is a grey crystalline solid with layered structure. Layers consist of two atomic sheets of antimony and three atomic sheets of tellurium and are held together by weak van der Waals forces. SbTe is a narrow-gap semiconductor with a band gap 0.21 eV; it is also a topological insulator, and thus exhibits thickness-dependent physical properties. Antimony telluride can be formed by the reaction of antimony with tellurium at 500–900 °C. Like other binary chalcogenides of antimony and bismuth, SbTe has been investigated for its semiconductor properties.