'Carpet' growth method yields long-sought 2D quantum material

Physicists have long sought a practical two-dimensional topological insulator: an ultrathin material that blocks current inside but conducts along its edges. A new 'carpet' growth method has now produced such a material.

• Inside a 2D topological insulator current is blocked, while edges conduct without loss
• Electrons with opposite spins travel in opposite directions along the edges
• This reduces scattering and energy loss compared with ordinary wires