A new kind of mirror is emerging from quantum physics labs, one that exists not as a chunk of polished glass but as a nanoscale film that can be switched between reflecting and transparent states.

In quantum physics, objects can exist in multiple states at the same time—a phenomenon known as quantum superposition, where a particle does not have a single definite value of position or momentum ...

SEAS and physics researchers report a new way to make ultra-smooth, microscopic mirrors that form high-performance optical resonators, or cavities. The technique harnesses silicon’s inherent ...