Quantum conformance test

Ortolano, Giuseppe; Boucher, Pauline; Degiovanni, I. P.; Losero, Elena; Genovese, M.; Berchera, I. Ruo

doi:10.1126/sciadv.abm3093

Cited by 5 publications

(15 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In particular a bipartite input state

irradiated by the transmitter will be mapped to the state

where

and

denotes the expectation value over the distribution

. The problem of discriminating two channels in the form defined by Equation ( 1 ) has been analysed in a different context in the QCT protocol [ 35 ]. Bipartite classical states are defined as the class of convex combinations of coherent states:

where

and

are M and L mode coherent states for signal and idler respectively.…”

Section: Methodsmentioning

confidence: 99%

“…In Ref. [ 35 ] it was shown how fixing the mean number of signal photons

, that in terms of Equation ( 2 ) defines the constraint

, classical states have a probability of error in the discrimination, for a cell prepared with equal probability in

, namely

, that is lower bounded by:

for any output measurement. This limit can be derived starting by the optimal probability of error in discriminating the states

and

given by the Helstrom bound [ 16 ]

, where

is the trace distance, and using the convexity of

to lower bound the probability of error.…”

Section: Methodsmentioning

confidence: 99%

“…After the measurement the optimal choice to recover the value of the bit y is to choose it as

, a condition that, using Bayes theorem and the fact that we assumed

, is equivalent to

, i.e., to maximize the likelihood. In terms of photon number distribution the probability of error of the recovery with a photon counting receiver,

, is given by [ 35 ]:

i.e., the probability of error is proportional to the overlap of the measurement outcome distributions

and

. For classical states the outcome distribution overlap cannot be reduced using idler modes, that are therefore not needed in this setting, and the overlap will be minimized for input signal states having a Poisson distribution in the photon number, such as a single mode coherent state [ 35 ].…”

Section: Methodsmentioning

confidence: 99%

“…In terms of photon number distribution the probability of error of the recovery with a photon counting receiver,

, is given by [ 35 ]:

i.e., the probability of error is proportional to the overlap of the measurement outcome distributions

and

, we can define a second informational limit:

…”

Section: Methodsmentioning

confidence: 99%

“…The scenario could be the one of a commercial production, with a limited single-cell accuracy, but with the possibility of an extremely precise post-production characterization. This problem studied here has some analogy to the recently proposed task of Quantum Conformance Test (QCT) [ 35 ], although the goal is different, the last one being devoted to the recognition of a defective production process with respect to a standard. In this work, we analyse the effect of possible defects in the construction of the memory on the readout performance and maximize the readout accuracy in presence of an imperfect, yet characterized, writing process.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Quantum Readout of Imperfect Classical Data

Ortolano

Berchera

2022

Sensors

Self Cite

View full text Add to dashboard Cite

The encoding of classical data in a physical support can be done up to some level of accuracy due to errors and the imperfection of the writing process. Moreover, some degradation of the stored data can happen over time because of physical or chemical instability of the system. Any readout strategy should take into account this natural degree of uncertainty and minimize its effect. An example are optical digital memories, where the information is encoded in two values of reflectance of a collection of cells. Quantum reading using entanglement, has been shown to enhances the readout of an ideal optical memory, where the two level are perfectly characterized. In this work, we analyse the case of imperfect construction of the memory and propose an optimized quantum sensing protocol to maximize the readout accuracy in presence of imprecise writing. The proposed strategy is feasible with current technology and is relatively robust to detection and optical losses. Beside optical memories, this work have implications for identification of pattern in biological system, in spectrophotometry, and whenever the information can be extracted from a transmission/reflection optical measurement.

show abstract

“…In particular a bipartite input state

irradiated by the transmitter will be mapped to the state

where

and

denotes the expectation value over the distribution

where

and

are M and L mode coherent states for signal and idler respectively.…”

Section: Methodsmentioning

confidence: 99%

“…In Ref. [ 35 ] it was shown how fixing the mean number of signal photons

, that in terms of Equation ( 2 ) defines the constraint

, classical states have a probability of error in the discrimination, for a cell prepared with equal probability in

, namely

, that is lower bounded by:

for any output measurement. This limit can be derived starting by the optimal probability of error in discriminating the states

and

given by the Helstrom bound [ 16 ]

, where

is the trace distance, and using the convexity of

to lower bound the probability of error.…”

Section: Methodsmentioning

confidence: 99%

“…After the measurement the optimal choice to recover the value of the bit y is to choose it as

, a condition that, using Bayes theorem and the fact that we assumed

, is equivalent to

, i.e., to maximize the likelihood. In terms of photon number distribution the probability of error of the recovery with a photon counting receiver,

, is given by [ 35 ]:

i.e., the probability of error is proportional to the overlap of the measurement outcome distributions

and

Section: Methodsmentioning

confidence: 99%

“…In terms of photon number distribution the probability of error of the recovery with a photon counting receiver,

, is given by [ 35 ]:

i.e., the probability of error is proportional to the overlap of the measurement outcome distributions

and

, we can define a second informational limit:

…”

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Quantum Readout of Imperfect Classical Data

Ortolano

Berchera

2022

Sensors

Self Cite

View full text Add to dashboard Cite

show abstract

Photon Statistics Modal Reconstruction by Detected and Undetected Light

et al. 2023

Self Cite

View full text Add to dashboard Cite

A novel technique is introduced for the reconstruction of multimode optical fields, based on simultaneously exploiting both the generalized Glauber's Kth‐order correlation function and a recently proposed anti‐correlation function (dubbed ) which is resilient to Poissonian noise. It is experimentally demonstrated that this method yields mode reconstructions with higher fidelity with respect to those obtained with reconstruction methods based only on 's, even requiring less “a priori” information. The reliability and versatility of this technique make it suitable for a widespread use in real applications of optical quantum measurement, from quantum information to quantum metrology, especially when one needs to characterize ensembles of single‐photon emitters in the presence of background noise (due, for example, to residual excitation laser, stray light or unwanted fluorescence).

show abstract

Quantum-Enhanced Pattern Recognition

Ortolano,

Napoli,

Harney

et al. 2023

Phys. Rev. Applied

Self Cite

View full text Add to dashboard Cite

The challenge of pattern recognition is to invoke a strategy that can accurately extract features of a dataset and classify its samples. In realistic scenarios this dataset may be a physical system from which we want to retrieve information, such as in the readout of optical classical memories. The theoretical and experimental development of quantum reading has demonstrated that the readout of optical memories can be dramatically enhanced through the use of quantum resources (namely entangled input-states) over that of the best classical strategies. However, the practicality of this quantum advantage hinges upon the scalability of quantum reading, and up to now its experimental demonstration has been limited to individual cells. In this work, we demonstrate for the first time quantum advantage in the multi-cell problem of pattern recognition. Through experimental realizations of digits from the MNIST handwritten digit dataset, and the application of advanced classical post-processing, we report the use of entangled probe states and photon-counting to achieve quantum advantage in classification error over that achieved with classical resources, confirming that the advantage gained through quantum sensors can be sustained throughout pattern recognition and complex post-processing. This motivates future developments of quantum-enhanced pattern recognition of bosonic-loss within complex domains.

show abstract

Quantum conformance test

Abstract: A practical quantum scheme is shown to have a performance beyond the classical limits in monitoring a manufacturing process.

Cited by 5 publications

References 43 publications

Quantum Readout of Imperfect Classical Data

Quantum Readout of Imperfect Classical Data

Photon Statistics Modal Reconstruction by Detected and Undetected Light

Quantum-Enhanced Pattern Recognition

Contact Info

Product

Resources

About