Comment on "Quantum Limits to Incoherent Imaging are Achieved by Linear Interferometry"

TL;DR

This paper critiques a previous linear interferometer construction, corrects the derivation, and presents an optimal configuration that reaches the quantum Fisher information limit for imaging multiple incoherent emitters.

Contribution

It identifies flaws in prior work, provides a corrected derivation, and proposes an optimal interferometric setup for quantum-limited imaging of incoherent sources.

Findings

The previous interferometer construction was flawed.

The corrected derivation achieves the quantum Fisher information limit.

The optimal configuration improves imaging precision for incoherent emitters.

Abstract

We show that the construction of the linear interferometer in the Supplemental Material of arXiv:1909.09581 is flawed, leading to a generally suboptimal solution. We then provide the correct derivation of the optimal interferometric configuration that achieves the quantum Fisher information limit for imaging N weak incoherent emitters.