Researchers at Oxford University have put Shrödinger cat into a box and claim it could have implications for quantum device design.
The research focused on the ‘fragility’ of quantum systems and the susceptibility to disturbances in the environment around them.
The Oxford-led team claim that they have found a way to use the sensitivity of quantum systems so that they can be used as sensors of extremely weak magnetic fields.
This sensitivity is often referred to as a “Shrödinger cat state” named after the famous thought experiment by physicist Erwin Shrödinger.
He imagined placing a cat in a sealed box with a lethal mechanism controlled by a random quantum event determining whether the cat was alive or dead.
Quantum theory makes the remarkable prediction that until the box is opened the cat is both alive and dead.
The researchers at Oxford effectively created a “quantum cat” based on the nuclear spins of a molecule being in one of two states, either ‘up’ or ‘down’, rather than dead or alive as in the case of Shrödinger's theoretical cat.
“To create our ‘quantum cat’ we took a star-shaped molecule with one central atom and nine atoms surrounding and applied radio frequency pulses to put it into an entangled state where all ten spins are spinning one way (‘alive’) and the other way (‘dead’) at the same time,’ said Dr John Morton of Oxford University’s Department of Materials, an author of the paper.
The work found that, compared to a non-entangled system, the molecule was many times more sensitive to the presence of a very weak magnetic field.
According to Professor Jonathan Jones of Oxford University’s Department of Physics, an author of the paper: “The next step is to investigate how a quantum sensor based on this work might be combined with existing sensors based on magnetic resonance.”
Such sensors are towed across the ocean floor looking for tiny, previously undetectable, telltale fluctuations in the Earth’s magnetic field which might suggest untapped reserves of gas or oil.