China’s new magnetic sensor can detect submarines from 500m away

Hall-effect sensors are already used in a number of everyday devices, including smartwatches, smartphones, car wheel-speed detectors, and hospital scanners. They work by generating a small voltage in the presence of a magnetic field. However, making these sensors smaller and more sensitive has always resulted in increased noise levels. This is similar to how turning up the volume on a radio also amplifies its hiss. The new Hall-effect magnetic sensor design by the Chinese scientists overcomes the long-standing sensitivity-noise trade-off. The device can detect weak magnetic fields without generating a lot of noise, making it ideal for use in wearables….