Chinese magnetic sensor breakthrough may help smartwatch detect submarine 500 metres deep

Picture a fisherman hauling in his nets on a calm morning at sea, when his smartwatch suddenly vibrates with an alert: “Magnetic anomaly detected – possible submarine passing 500 metres below.”
Far‑fetched as it sounds, Chinese scientists have just taken a decisive step towards making that scenario real.
A team from the Hefei Institutes of Physical Science and the Ningbo Institute of Materials Technology and Engineering, both under the Chinese Academy of Sciences (CAS), has created a Hall‑effect...