Tying Quantum Knots with an Optical Clock

(JILA.colorado.edu) The holy grail of modern quantum science is to make a stable quantum computer. Now an experiment is on its way to create a quantum computer that is stable and can last longer using the sophisticated optical clock at JILA.
The first step to creating the quantum computer is tricky. The qubits need to be in a cluster state, a neat configuration with all the atoms properly entangled. “The hard part is connecting the qubits because that is necessary to generate entanglement,” said Mikhail Mamaev, a JILA graduate student. “And experimentally it’s very difficult to do.”
Now there may be a quick and easy way to do it. Mamaev has proposed a way to create highly-entangled cluster states using an optical atomic clock’s laser to weave atoms into a cluster state. “We have this clock with super-high coherence, super-clean, super-orderly.” The clock can create those cluster states in a hundred milliseconds. Not only can it create these cluster states, it can keep them stable for ten seconds. That’s a long time in the quantum world, long enough to run measurements. And by making a simple measurement, the entangled links break, giving physicists information.