Moiré than meets the eye

Stacking single layers of sub-nanometer-thick semiconductor materials, known as transition metal dichalcogenides, can generate a moiré potential – a “seascape” of potential energy with regularly repeating peaks and valleys. These peaks and valleys were previously thought to be stationary, but now, researchers from the Molecular Foundry, a user facility at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory, and the University of California, Berkeley, along with international collaborators, have shown that the moiré potentials that emerge when transition metal dichalcogenides are stacked are constantly moving, even at low temperatures. Their discovery contributes to foundational knowledge in materials science and holds promise for advancing the stability of quantum technologies, because controlling moiré potentials could help mitigate decoherence in qubits and sensors. (Decoherence occurs when interference causes the quantum state and its information to be lost.)