Scaling Laws for the Sensitivity Enhancement of Non-Gaussian Spin States

We identify the large-N scaling of the metrological quantum gain offered by over-squeezed spin states that are accessible by one-axis twisting, as a function of the preparation time. We further determine how the scaling is modified by relevant decoherence processes and predict a discontinuous change of the quantum gain at a critical preparation time that depends on the noise. Our analytical results provide recipes for optimal and feasible implementations of quantum enhancements with non-Gaussian spin states in existing experiments, well beyond the reach of spin squeezing.

Automated summary

The study identifies the large-N scaling of metrological quantum gain provided by over-squeezed spin states and predicts a discontinuous change in quantum gain at a critical preparation time. It provides analytical recipes for optimal implementation of quantum enhancements with non-Gaussian spin states in existing experiments.