  We demonstrate quantum logic enhanced sensitivity for a macroscopic ensemble
of solid-state, hybrid two-qubit sensors. We achieve a factor of 30 improvement
in signal-to-noise ratio, translating to a sensitivity enhancement exceeding an
order of magnitude. Using the electronic spins of nitrogen vacancy (NV) centers
in diamond as sensors, we leverage the on-site nitrogen nuclear spins of the NV
centers as memory qubits, in combination with homogeneous bias and control
fields, ensuring that all of the ${\sim}10^9$ two-qubit sensors are
sufficiently identical to permit global control of the NV ensemble spin states.
We find quantum logic sensitivity enhancement for multiple measurement
protocols with varying optimal sensing intervals, including XY8 dynamical
decoupling and correlation spectroscopy, using a synthetic AC magnetic field.
The results are independent of the nature of the target signal and broadly
applicable to metrology using NV centers and other solid-state ensembles. This
work provides a benchmark for macroscopic ensembles of quantum sensors that
employ quantum logic or quantum error correction algorithms for enhanced
sensitivity.
