Physics: 'quantum radio' breakthrough could save your life in a fire, flood or earthquake

For the first time, physicists have demonstrated that "quantum radio" could function in situations where regular radio signals are no match for high levels of interference—underwater, underground, in remote landscapes or even collapsed buildings.

Researchers from the National Institute of Standards and Technology and the department of physics at the University of Colorado, Boulder, arrived at the breakthrough by experimenting with very low-frequency radio. The lower a signal’s frequency, the farther it travels, but at the expense of the precision afforded with higher frequencies. 

The researchers built a direct-current magnetometer that detects the "spin" of certain atoms using polarized light. Because the atoms are highly sensitive and respond quickly, the resulting quantum sensors would be able to enhance very low-frequency radio with the best of both worlds—precise signals at an ideal bandwidth. A paper detailing the work was published in the Review of Scientific Instruments.

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