Researchers at University of Tsukuba measured tiny magnetic fields with unprecedented speed. By monitoring spins at Nitrogen-Vacancy (NV) centers along using ultrafast spectroscopy. They hence demonstrated how ultrafast spectroscopy can be used to improve the temporal resolution of quantum sensors.
This work may allow for the advancement of the field of ultra-high accuracy measurements known as quantum metrology, as well as “spintronic” quantum computers that operate based on electron spins.
The team used an “inverse Cotton-Mouton” effect to test their method. The normal Cotton-Mouton effect occurs when a transverse magnetic field creates birefringence, which can change linearly polarized light into having an elliptical polarization. In this experiment, the scientists did the opposite, and used light of different polarizations to create tiny controlled local magnetic fields.
The work has been published in APL Photonics.