Quantum metrology via mitigation of single-photon loss using an engineered nonlinear oscillator

TL;DR

This paper demonstrates that engineered two-photon loss in a Kerr resonator significantly mitigates the effects of single-photon loss, extending high-sensitivity quantum metrology windows and stabilizing non-Gaussian quantum resources.

Contribution

It introduces a hybrid model with engineered two-photon loss that actively mitigates photon loss effects, enabling autonomous, robust quantum sensing without feedback control.

Findings

Engineered two-photon loss converts damped oscillations into smooth decay, extending sensing windows.

High-precision sensing is sustained by dissipatively stabilized non-Gaussian cat states.

The approach offers a scalable, autonomous method for robust quantum metrology in various platforms.

Abstract

The fragility of quantum metrological advantages under loss remains a major barrier to practical quantum sensing. For a two-photon-driven (TPD) Kerr resonator (TPD-Kerr model) subject to unavoidable single-photon loss (SPL), both the quantum Fisher information gain and squeezing level exhibit hard-to-track long-lived damped oscillations, restricting useful sensing and squeezing to extremely short time windows. We show that adding engineered two-photon loss (ETPL) -- forming a TPD-Kerr-ETPL hybrid model -- significantly mitigates these oscillations and converts the decay into a smooth, monotonic drop. This extends the high-sensitivity windows by over an order of magnitude. Moreover, we reveal a temporal hierarchy of quantum resources: the initial boost in metrological sensitivity arises from Gaussian squeezing, while sustained high-precision sensing stems from dissipatively stabilized non-Gaussian even-parity cat states. Crucially, only in models that include ETPL -- such as the TPD-Kerr-ETPL and TPD-ETPL systems -- does the dynamics actively mitigate SPL's detrimental effects, transforming damped oscillation into a smooth, easily trackable trajectory and enabling a prolonged, usable metrological window. Our approach transcends encoding-based or feedback-controlled schemes, offering a fully autonomous route to high-precision measurement without real-time feedback control. This establishes a general design principle: engineered loss, combined with appropriate driving, can actively preserve metrologically useful non-Gaussian quantum resources even in the presence of SPL -- paving the way toward robust, scalable quantum sensors in superconducting circuits, optomechanics, and trapped-ion platforms.