Noise is annoying, whether you’re trying to sleep or exploit the laws of quantum physics. Although noise from environmental disturbances will always be with us, a team including scientists at the National Institute of Standards and Technology (NIST) may have found a new way of dealing with it at the microscopic scales where quantum physics reigns. Addressing this noise could make possible the best sensors ever made, with applications ranging from health care to mineral exploration.
By taking advantage of quantum phenomena known as superposition and entanglement, researchers can measure subtle changes in the environment useful for everything from geology to GPS. But to do this, they must be able to see through the noise caused by environmental sources such as stray magnetic fields to detect, for example, an important signal from the brain.
New findings, detailed today in Physical Review Letters, would enable interlinked groups of quantum objects such as atoms to better sense the environment in the presence of noise. A horde of unlinked quantum objects can already outperform a conventional sensor. Linking them through the process of quantum entanglement can make them perform better still. However, entangling the group can make it vulnerable to environmental noise that causes errors, making the group lose its additional sensing advantage.