Information technologies of the future will likely use electron spin -- rather than electron charge -- to carry information. But first, scientists need to better understand how to control spin and learn to build the spin equivalent of electronic components, from spin transistors, to spin gates and circuits. Now, researchers have developed a technique to control and measure spin voltage, known as spin chemical potential. The technique, which uses atomic-sized defects in diamonds to measure chemical potential, is essentially a nanoscale spin multimeter that allows measurements in chip-scale devices. The research is published in Science . "There is growing interest in insulating materials that can conduct spin," said Amir Yacoby, Professor of Physics in the Department of Physics and of Applied Physics at Harvard John A. Paulson School of Engineering and Applied Sciences and senior author of the paper. "Our work develops a new way to look at these spins in material...