Overcoming resolution limits with quantum sensing

Abstract

The field of quantum sensing explores the use of quantum phenomena to measure a broad range of physical quantities, of both static and time-dependent types. While for static signals the main figure of merit is sensitivity, for time dependent signals it is spectral resolution, i.e. the ability to resolve two different frequencies. Here we study this problem, and develop new superresolution methods that rely on quantum features. We first formulate a general criterion for superresolution in quantum problems. Inspired by this, we show that quantum detectors can resolve two frequencies from incoherent segments of the signal, irrespective of their separation, in contrast to what is known about classical detection schemes. The main idea behind these methods is to overcome the vanishing distinguishability in resolution problems by nullifying the projection noise.

A perspective on multiparameter quantum metrology: From theoretical tools to applications in quantum imaging

“…The theory of precise measurements of a small transverse separation of two incoherent point sources has been exhaustively covered in [137][138][139][140], and generalized in terms of quantum superresolution [141]. This two-source model is useful for understanding many subtleties, and is actually relevant for some applications -for instance, in astronomical observations [92] and imaging of luminescent targets [142,143].…”

Quantum sensing of open systems: Estimation of damping constants and temperature

“…Through a generalization of the classical framework to quantum mechanics [3][4][5][6], it has been realized that quantum probes, prepared in states with features like squeezing and entanglement, help to increase the precision of the estimation, for the same amount of resources (which could be the number of atoms or photons used in the estimation). This has been relevant, for instance, for extending the coverage of gravitational-wave interferometers, with the use of squeezed light [5,7] or of entangled states [8], for increasing the magnetic sensitivity with spin squeezing [9], for optimal thermometry [10], for detecting weak electric fields with superpositions of Rydberg states [11], for achieving quantum-enhanced contrast and resolution in biological microscopy [12,13], and for superresolution of spatial separation and frequency [14]. Quantum sensing [15,16] involves the exploration of subtle quantum effects to increase the precision of parameter estimation.…”

Design of an on-Chip Room Temperature Group-IV Quantum Photonic Chem/Bio Interferometric Sensor Based on Parity Detection

“…While for static signals the main figure-of-merit is the sensitivity, for time-dependent signals it is the spectral resolution, i.e. the ability to resolve two different frequencies [ 1 ]. In this context, new super-resolution methods that rely on quantum features, have been recently developed [ 1 ].…”

“…the ability to resolve two different frequencies [ 1 ]. In this context, new super-resolution methods that rely on quantum features, have been recently developed [ 1 ]. However, in the chemical/bio sensing scenario, exceptional sensitivity is required.…”

“…When a phase shift ( ) is induced on one arm of the MZI, the output records an oscillatory fringe pattern with a periodicity given by half wavelength ( ), usually referred as the “Rayleigh criterion” for phase measurements. However, this limit can be surpassed using different types of quantum states or measurement schemes [ 1 ], [ 9 , 10 , 11 ]. In this sense, the goal is to recover the phase value by measuring the signals emerging from the MZI, while using a limited amount of resources by setting an upper limit on the average (maximum) number of photons incoming at the MZI inputs.…”