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Topological insulators are band insulators with large spin–orbit coupling, in which surface states give rise to gap-traversing modes that are robust against scattering. Theory now predicts that screw dislocations and other types of defects can give rise to one-dimensional topologically protected states in such systems. Article p298 Cover design by David Shand
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Topological insulators are band insulators in which spin–orbit coupling takes the role of the applied magnetic field in the integer quantum Hall effect. Theory now predicts that dislocations in such systems can give rise to one-dimensional topologically protected states, resembling helical modes at the edge of a two-dimensional quantum spin Hall insulator.
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