Optimal estimation of losses at the ultimate quantum limit with non-Gaussian states
arXiv:0807.3958 · doi:10.1103/PhysRevA.79.040305
Abstract
We address the estimation of the loss parameter of a bosonic channel probed by arbitrary signals. Unlike the optimal Gaussian probes, which can attain the ultimate bound on precision asymptotically either for very small or very large losses, we prove that Fock states at any fixed photon number saturate the bound unconditionally for any value of the loss. In the relevant regime of low-energy probes, we demonstrate that superpositions of the first low-lying Fock states yield an absolute improvement over any Gaussian probe. Such few-photon states can be recast quite generally as truncations of de-Gaussified photon-subtracted states.
4 pages, 3 figures
References in corpus (11)
- Resolving photon number states in a superconducting circuit
- Reconstruction of non-classical cavity field states with snapshots of their decoherence
- Progressive field-state collapse and quantum non-demolition photon counting
- Generating Single Microwave Photons in a Circuit
- Increasing entanglement between Gaussian states by coherent photon subtraction
- Optimal quantum estimation of loss in bosonic channels
- Continuous variable quantum teleportation with non-Gaussian resources
- The optimal cloning of quantum coherent states is non-Gaussian
- Tomographic reconstruction of the single-photon Fock state by high-frequency homodyne detection
- Squeezed vacuum as a universal quantum probe
- Continuous variable quantum teleportation with sculptured and noisy non-Gaussian resources