Rui Wu

A quantum chip is like a musical instrument that goes out of tune at the slightest touch. In devices made from strained germanium, a material where atoms are slightly stretched for better conductivity, the main source of off-key notes is defects at the interface between the semiconductor and the insulating layer.

Inside a piece of magnetic material, electron spins, tiny magnetic arrows, usually arrange into simple patterns. Sometimes they swirl into vortices, like water down a drain, and these vortices can tie themselves into knots.

The surface of the uranium compound UTe2 crystal looks like a frozen sea: in some places, electrons move freely; in others, they get stuck near atoms. A scanning tunneling microscope, a device that probes the surface with an atomically sharp tip and senses individual electrons, revealed that this landscape is not random.

In the constellation Orion, in the cloud of gas and dust L1641, the young star PR Ori B suddenly flared up like a furnace that someone had thrown fuel into. Its brightness rose fivefold, and astronomers watched for the first time as a fuor was born, a rare event in which a star begins greedily swallowing material from the surrounding disk.