‘Carpet’ growth method yields long-sought 2D quantum material

For decades, physicists have sought a practical two-dimensional topological insulator: an ultrathin material whose interior blocks electricity but whose edges conduct it. In ordinary wires, electrons constantly bounce off imperfections, losing energy. But along the edges of a 2D topological insulator, electrons with opposite spins travel in opposite directions, like cars in one-way lanes, so

Quantum physicists trace a century of controlling spin

A concept from the field of quantum mechanics, spin is a property of particles that has no direct counterpart in everyday experience. Since the early 20th century, researchers have learned to manipulate it deliberately by means of precisely shaped electromagnetic pulses. This has resulted in two technologies that are widespread today: magnetic resonance imaging (MRI)