Superfluid qubits in ultracold atom systems

Abstract

If there's one thing that makes for an exciting subject, it's the physics of extremes. Contemplating extreme speeds brought us revolutionary theory of special relativity. There is also a whole world of strange effects on the other end of the spectrum, the realm of the extremely slow and the extremely cold. As you go from steam to water to ice, the temperature of H2O goes down but at the same time the atoms are moving more slowly. Physically, temperature is just another way of talking about the average speed of atoms. Because there is a slowest possible speed, no speed, there is a corresponding lowest possible temperature, which we call absolute zero. Ice, we all learn in school, freezes at 0 Celsius. Going further down the temperature scale, nitrogen in the air will liquefy at -196 Celsius, the temperature of outer space is -270 Celsius, and absolute zeroitself is -273.15 ...