Topological insulators conduct on the surface but insulate in the bulk
Topological insulator
Topological insulators conduct on the surface but insulate in the bulk
Topological insulators have a unique property where their interior acts as an electrical insulator while their surface conducts electricity. This behavior is due to the presence of an energy gap between the valence and conduction bands, which are "twisted" in a way that prevents a continuous transformation into a trivial insulator without closing the band gap. This unique band structure results in conducting edge states that are protected against local perturbations.
Example
Bismuth selenide (Bi2Se3) is a well-known topological insulator that exhibits this property. Its surface electrons can move freely, making it useful for applications in electronics and spintronics.
Understanding topological insulators is crucial for developing new technologies that leverage their unique conductive properties on the surface while maintaining insulation in the bulk.
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