Abstract
In the past ten years, solid state quantum bits have opened a window towards revolutionary applications. Much of this progress has been achieved thanks to the nitrogen-vacancy (NV) center in diamond, a color defect with a stable ground state electron spin, which can be read out optically by laser excitation and detection of its fluorescence intensity.
I will review the applications that have been demonstrated with this qubit, focusing notably on nuclear magnetic resonance spectroscopy on samples as small as a single biomolecule and use of NV centers as labels for functional imaging and super-resolution microscopy.
I will finally speculate on the future directions of the field: how much more powerful could these applications become, if an optically readable qubit could be found in a single molecule rather than a solid-state material? How could physics and chemistry possibly achieve this goal?