With the help of DC-SQUIDS (superconducting quantum interference device), researchers of Cornell University and Oxford University have been successful in detecting the noise in magnetic monopoles.
Magnetic monopoles are hypothetical elementary particles with quantized magnetic charge. In principle, a magnetic monopole can be detected by the quantized jump in the magnetic flux it generates when passing through a SQUID.
The development of a SQUID-based flux noise spectrometer and measurements of the frequency and temperature dependence of magnetic-flux noise generated by Dy2Ti2O7 crystals are reported. Almost all of the features of magnetic-flux noise predicted for magnetic monopole plasmas, including the existence of intense magnetization noise and its characteristic frequency and temperature dependence were detected. Interestingly enough, the magnetic monopole flux noise amplified by SQUID is audible to humans, because the generation-recombination time constant for Dy2Ti2O7 is in the millisecond range.

Please find further details in the full article, available at: https://www.nature.com/articles/s41586-019-1358-1

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