  We propose to use a dissipatively engineered nitrogen vacancy (NV) center as
a mediator of interaction between two nuclear spins that are protected from
decoherence and relaxation of the NV. Under ambient conditions this scheme
achieves highly selective high-fidelity quantum gates between nuclear spins in
a quantum register even at large NV-nuclear distances. Importantly, this method
allows for the use of nuclear spins as a sensor rather than a memory, while the
NV spin acts as an ancillary system for the initialization and read out of the
sensor. The immunity to the decoherence and relaxation of the NV center leads
to a tunable sharp frequency filter while allowing at the same time the
continuous collection of the signal to achieve simultaneously high spectral
selectivity and high signal-to-noise ratio (SNR).
