David Mandrus

TL;DR: This work reports the unambiguous observation and electrostatic tunability of charging effects in positively charged, neutral and negatively charged excitons in field-effect transistors via photoluminescence and finds the charging energies for X(+) and X(-) to be nearly identical implying the same effective mass for electrons and holes.

TL;DR: The ability to address coherence, in addition to valley polarization, is a step forward towards achieving quantum manipulation of the valley index necessary for coherent valleytronics.

TL;DR: These cleavable materials provide the ideal platform for exploring magnetism in the two-dimensional limit, where new physical phenomena are expected, and represent a substantial shift in the authors' ability to control and investigate nanoscale phases.

TL;DR: Results suggest that the origin of the observed effects is interlayer excitons trapped in a smooth moiré potential with inherited valley-contrasting physics, and presents opportunities to control two-dimensional moirÉ optics through variation of the twist angle.

TL;DR: A new lasing strategy is reported: an atomically thin crystalline semiconductor—that is, a tungsten diselenide monolayer—is non-destructively and deterministically introduced as a gain medium at the surface of a pre-fabricated PCC, allowing an optical pumping threshold as low as 27 nanowatts at 130 kelvin similar to the value achieved in quantum-dot PCC lasers.