Scientists Develop Room-Temperature, Ultra-Sensitive Miniature Magnetometer
An international research team, including contributors from Peking University, has developed a novel miniature magnetometer. This device can detect extremely weak magnetic fields at room temperature, paving the way for advancements in various scientific fields.
An international research team, with participation from Peking University, has developed a new type of miniature magnetometer capable of detecting extremely faint magnetic field signals at room temperature. The device, detailed in the journal Science, boasts a sensitivity of 32 femtotesla per square root of hertz (fT/√Hz), comparable to established SQUID and atomic magnetometers.
The core of the magnetometer is a tiny permanent magnet, smaller than a grain of rice, suspended in a vacuum chamber. This freely levitating setup minimizes interference from mechanical vibrations, a common issue in traditional sensors. Changes in the magnet's orientation due to external magnetic fields are detected using a laser beam reflecting off its surface, with any deflection measured.
Researchers significantly reduced thermal noise by employing a specially designed base substrate. This improvement allows for the detection of even weaker signals. Crucially, the device operates without the need for cryogenic cooling or magnetic shielding, making it suitable for use in standard laboratory environments.
The new magnetometer has potential applications in biosensing, chemical analysis, and fundamental physics research, owing to its ability to function under normal operating conditions.