Chinese-German team builds ultra-sensitive ‘floating compass’ to hunt dark matter

Chinese researchers have developed a table-top magnetic sensor that operates at room temperature and can spot magnetic signals a billion times fainter than the Earth’s own field.The Levitated Magnet Magnetometer (LeMaMa) functions like a compass with a needle that floats in mid-air with virtually no friction. By tracking the needle’s tiny deflections, the team can measure magnetic fields down to the femtotesla level – an advance that could widen the hunt for elusive dark matter particles or monitor brain signals.“The combination of room-temperature operation, tiny components and high sensitivity makes LeMaMa promising for fundamental physics experiments,” Ji Wei, assistant professor at Peking University’s school of physics and corresponding author of the study, told Guangming Daily on August 17.