By Peter Weiss
When a patient undergoes magnetic resonance imaging (MRI), the scanner makes tissues visible by tapping into a magnetlike property of many trillions of protons in the patient’s body. Known as spin, this quantum-mechanical trait also shows up in electrons, atomic nuclei, and many other elementary particles. Now, scientists have devised an ultrasensitive MRI technique and used it to detect the spin of a single electron.
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Daniel Rugar and his colleagues at IBM Almaden Research Center in San Jose, Calif., report their feat in the July 15 Nature.