Microwave-Free 13 C Hyperpolarization of Diamond Particles Enabled by Magic Angle Spinning and NV Centers
This work achieved microwave-free hyperpolarization of 13C nuclei in randomly oriented diamond particles using optical pumping from NV centers under high-field Magic Angle Spinning (MAS). By exploiting rotation-induced level anticrossings in a three-spin system, the method reached polarization enhancements up to 280-fold. This provides an efficient way to achieve ultrasensitive NMR at room temperature.