Raw datasets and scripts to produce article's figures 2-4.

Theoretical proposals for enhancing optical sensing, including the bosonic analogue of the Kitaev model, predict that nonreciprocal dynamics can yield an enhanced signal-to noise ratio. However, experimental demonstrations have so far been limited to small lattices.

Here we show an optical sensor in which nonreciprocal light propagation enables the detection of weak perturbations with a signal-to-noise ratio, linked to the quantum Fisher information extracted per input photon, that scales exponentially with system size. Our approach encodes two coupled Hatano–Nelson chains that realize an effective bosonic Kitaev model within the resonant modes of an electro-optic frequency comb. Nonreciprocal propagation in frequency space is achieved via simultaneous phase and amplitude modulation of the intracavity field.