Entropic nonclassicality and quantum non-Gaussianity tests via beam splitting

Park, Jiyong; Lee, Jaehak; Nha, Hyunchul

doi:10.1038/s41598-019-54110-4

Cited by 8 publications

(5 citation statements)

References 62 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…If the following condition is satisfied for a single-mode quantum state

, it signifies that

is quantum non-Gaussian:

where

denotes the phase-randomization,

represents the loss channels with the effective transmittance

, and

is the mean photon number of

. We can derive Equation ( 29 ) by reformulating the quantum non-Gaussianity condition in [ 58 ]:

Starting from the fact that the reference Gaussian state of

is a thermal state with mean photon number

, it is straightforward to derive

and

, which yields

It signifies that a sufficiently large decrease in

under a loss channel is only possible for quantum non-Gaussian states.…”

Section: A Lower Bound For Single-mode Non-gaussianitymentioning

confidence: 99%

“…The quantum non-Gaussianity measures have been proposed by using the Wigner logarithmic negativity [ 48 , 49 ], quantum relative entropy [ 50 ], stellar representation [ 51 ], and robustness [ 52 ]. Additionally, quantum non-Gaussianity witnesses have been theoretically proposed [ 47 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 ] and experimentally demonstrated [ 62 , 63 , 64 , 65 , 66 , 67 ] to certify quantum non-Gaussianity efficiently. Here, our main interest is in non-Gaussianity measures that characterize the difference between a quantum state and its reference Gaussian state.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Estimating Non-Gaussianity of a Quantum State by Measuring Orthogonal Quadratures

Park

2022

Entropy

Self Cite

View full text Add to dashboard Cite

We derive the lower bounds for a non-Gaussianity measure based on quantum relative entropy (QRE). Our approach draws on the observation that the QRE-based non-Gaussianity measure of a single-mode quantum state is lower bounded by a function of the negentropies for quadrature distributions with maximum and minimum variances. We demonstrate that the lower bound can outperform the previously proposed bound by the negentropy of a quadrature distribution. Furthermore, we extend our method to establish lower bounds for the QRE-based non-Gaussianity measure of a multimode quantum state that can be measured by homodyne detection, with or without leveraging a Gaussian unitary operation. Finally, we explore how our lower bound finds application in non-Gaussian entanglement detection.

show abstract

“…If the following condition is satisfied for a single-mode quantum state

, it signifies that

is quantum non-Gaussian:

where

denotes the phase-randomization,

represents the loss channels with the effective transmittance

, and

is the mean photon number of

. We can derive Equation ( 29 ) by reformulating the quantum non-Gaussianity condition in [ 58 ]:

Starting from the fact that the reference Gaussian state of

is a thermal state with mean photon number

, it is straightforward to derive

and

, which yields

It signifies that a sufficiently large decrease in

under a loss channel is only possible for quantum non-Gaussian states.…”

Section: A Lower Bound For Single-mode Non-gaussianitymentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Estimating Non-Gaussianity of a Quantum State by Measuring Orthogonal Quadratures

Park

2022

Entropy

Self Cite

View full text Add to dashboard Cite

show abstract

“…Homodyne detection provides a sensitive probe of the rotated quadrature, which is independent of detection efficiency. Homodyne detection is a conceivable projective measurement in terms of quantum mechanical operators [24,[28][29][30].…”

Section: Introductionmentioning

confidence: 99%

Generating superpositions of quantum states via a beam splitter with position measurement

Ren,

Zhang

2023

Phys. Scr.

View full text Add to dashboard Cite

We use the quadrature measurement to generate the novel nonclassical states via the beam splitter with two input states, i.e., a Fock state and a vacuum state. It is interesting to find that the desired target states are the Hermite polynomial excited vacuum states. Our results have shown that the zero-position detection for the position detector, the little photon number in the input state, and the high transmittance of the beam splitter (BS) are beneficial to improve the detection efficiency of finding the output states. The proposed states quantum statistical properties and squeezing effects are also studied in detail via different criteria. Our numerical analysis demonstrates that the output quantum states are new nonclassical states. Compared with the method of photon catalysis, position detection is easier to realize in experiments. Therefore, the results in this paper shall provide theoretical support for the experimental generation of several new nonclassical states.

show abstract

“…To our knowledge, even though some works [43,47,48] have already been carried out on obtaining SMNc conditions from two-mode entanglement criteria, the following important treatments/demonstrations are absent in the literature. Obtaining the matrix forms for a (i, ii) measure/condition in terms of â 2 and â † â and carrying out an optimization for (i, ii) SMNc measure/condition, measurement of the nonclassicality of, e.g.…”

Section: Introductionmentioning

confidence: 99%

Measuring nonclassicality of single-mode systems

Tașgın¹

2020

J. Phys. B: At. Mol. Opt. Phys.

View full text Add to dashboard Cite

Nonclassicality of a single-mode state can be quantified by the entanglement (potential) the state creates at the output of a beam splitter. Thus, beam splitter transformation can be utilized for obtaining single-mode nonclassicality conditions (quantifications) from two-mode entanglement criteria (measures). Here, (i) we employ this relation to quantify the single-mode nonclassicality (SMNc) of a nonlinear crystal field generating second harmonic signals. (ii) We also manage to witness the SMNc of superradiant emission, a non-Gaussian state, in a Dicke phase transition. Entanglement potential, at the beam splitter output, is obtained in terms of measurable single-mode quantities. Thus, presence of a beam splitter in an experiment is not necessary. Employing the beam splitter method, one can also utilize hybrid entanglement criteria as SMNc conditions working well in different classes of single-mode states. (iii) We also work on essentials of the entanglement-SMNc relation: one obtains the generalized squeezing condition ⟨â†â⟩ < |⟨â2⟩| as the SMNc condition when an optimized form of Duan–Giedke–Cirac–Zoller criterion [PRL 84, 2722] is used at the output of the beam splitter.

show abstract

Entropic nonclassicality and quantum non-Gaussianity tests via beam splitting

Cited by 8 publications

References 62 publications

Estimating Non-Gaussianity of a Quantum State by Measuring Orthogonal Quadratures

Estimating Non-Gaussianity of a Quantum State by Measuring Orthogonal Quadratures

Generating superpositions of quantum states via a beam splitter with position measurement

Measuring nonclassicality of single-mode systems

Contact Info

Product

Resources

About