Pith. sign in

REVIEW 3 major objections 6 minor 67 references

Thermal Quantum Correlations in Coupled Andreev Spin Qubits: Interplay of Superconducting Phase and Spin-Orbit Interaction

T0 review · 3 major / 6 minor · reviewed 2026-07-31 · grok-4.5

Pith's one-line read Superconducting phase, tunneling, and spin–orbit coupling periodically control and thermally protect quantum correlations in Andreev spin qubits.

desk verdict Competent first LQFI/LQU maps on the Spethmann Andreev dimer; spectrum is fine, but the gap story is almost tautological and device claims sit on the projected-model regime. read the letter →

arxiv 2607.24521 v1 pith:IZ73A4L5 submitted 2026-07-27 quant-ph

classification quant-ph
keywords AndreevspinqubitsthermalquantumcorrelationslocalFisherinformationuncertaintysuperconductingphasespin-orbitinteractiontunnelinghybriddevices
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

This paper maps how thermal quantum correlations behave in two coupled Andreev spin qubits—hybrid devices that combine superconducting leads with spin degrees of freedom on quantum dots. Using two standard measures of nonclassical correlation (local quantum Fisher information and local quantum uncertainty), the authors show that raising temperature steadily washes correlations out, while stronger tunneling and stronger spin–orbit interaction keep them alive longer. The superconducting phase difference acts as a dial: it periodically strengthens or weakens the effective exchange couplings, creating constructive and destructive interference regimes that turn correlations up or down. The microscopic reason is simple—the same parameters that enlarge the gap between the ground state and the first excited state keep the system sitting in its correlated ground state and suppress thermal mixing. The work therefore offers concrete knobs—phase, tunneling, and spin–orbit angle—for protecting quantum resources in hybrid superconducting devices.

What carries the argument

The effective two-spin Andreev Hamiltonian (with staggered field h and couplings Jz, Jx, JDM set by phase φ, spin–orbit angle α, and tunneling-scale J) and its exact thermal X-state density matrix; LQFI and LQU are evaluated from that state, and their peaks are shown to coincide with maxima of the gap ΔE = E1 − E0.

What would settle it

Measure LQFI or LQU (or a proxy such as entanglement or discord) versus superconducting phase at fixed low temperature: if the correlations do not peak near φ = 0, 2π and collapse near φ = ±π, or if increasing tunneling or spin–orbit angle fails to enlarge the relevant gap and slow the thermal decay, the claimed mechanism is wrong.

Watch

Extended reading notes

Core claim

Thermal LQFI and LQU in the effective Andreev spin-qubit Hamiltonian are periodically controlled by the superconducting phase through modulation of the exchange couplings, are enhanced and made more temperature-robust by larger tunneling J and spin–orbit angle α, track the ground–first-excited energy gap that suppresses thermal excitation of the correlated ground state, and satisfy LQFI ≥ LQU everywhere in the scanned parameter space.

Load-bearing premise

The whole analysis rests on the effective two-spin Hamiltonian remaining valid—weak tunneling, large on-site repulsion, and singly occupied dots—so that real devices are still described by those four exchange parameters.

Editorial extensions

If this is right

  • Phase biasing a Josephson junction that hosts Andreev spin qubits can be used as an on-chip switch to turn thermal quantum correlations on or off.
  • Larger tunneling and spin–orbit strength widen the useful temperature window in which those correlations survive.
  • Because LQFI stays above LQU, metrological figures of merit remain at least as informative as skew-information measures for these devices.
  • Device design that deliberately enlarges the ground-to-first-excited gap will automatically protect the correlated ground state against thermal noise.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • The same phase-interference mechanism should appear in multi-qubit Andreev arrays, offering a route to phase-tunable multipartite correlations without extra control lines.
  • If the gap-protection picture is general, any hybrid superconductor–spin Hamiltonian whose spectrum can be phase-tuned could inherit the same thermal robustness recipe.
  • Experimental tomography of the two-dot thermal state versus φ would simultaneously test both the effective-model reduction and the LQFI/LQU hierarchy.
Share X Bluesky LinkedIn Reddit HN

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

3 major / 6 minor

Summary. The paper computes thermal quantum correlations (LQFI and LQU) for two coupled Andreev spin qubits described by the effective two-spin Hamiltonian of Spethmann et al. (PRB 106, 115411 (2022)), which contains an Ising exchange Jz, an XY exchange Jx, a Dzyaloshinskii–Moriya term JDM, and a staggered field h, all functions of a superconducting phase φ, spin-orbit angle α, and effective coupling J. The authors diagonalize the 4×4 Hamiltonian, construct the Gibbs state in closed X-form, and map LQFI and LQU over the (φ, α, J, T) parameter space. Main claims: correlations decay monotonically in T; grow with J and α; are periodically modulated by φ (maxima near φ=0, minima near φ=±π); track the ground–first-excited gap; and obey LQFI ≥ LQU everywhere.

Significance. If the analysis holds, the paper provides a complete analytic characterization of two standard correlation quantifiers for a relevant effective model of a contemporary hybrid platform, with closed-form density matrix, partition function, and correlation expressions that are independently verifiable and produce concrete, falsifiable predictions (phase periodicity, α- and J-dependence, thermal decay scales). The computation is routine in method but correct in execution and fills a genuine, if modest, gap: LQFI/LQU had not been mapped for this Hamiltonian. I verified the central algebraic point: using Eq. (29), χ² = 4h² + Jx² + JDM² = 4J²(1 + cosφ cos(α/2))² = Jz², so χ = Jz exactly (Jz ≥ 0), the spectrum E0 = −3Jz/4, E1=E2=E3 = Jz/4 in Eq. (34) is exact, and Z in Eq. (37) is consistent with it. A flagged concern that Eq. (34) is an "incorrect spectrum" does not, on checking, land. The significance is incremental rather than transformative: standard measures applied to a published effective Hamiltonian, with the microscopic device physics absorbed into a single effective J.

major comments (3)
  1. [§5, Fig. 8; Abstract] §5, Fig. 8 and Abstract: the 'gap-protection mechanism' is tautological as presented. Since χ = Jz identically (from Eq. (29): χ² = 4h²+Jx²+JDM² = 4J²(1+cosφ cos(α/2))² = Jz²), the gap ∆E = E1−E0 = Jz exactly. The gap and the exchange scale controlling the correlations are therefore the same quantity, so the statement that 'enhancement of correlations is associated with an increased energy gap' is a restatement of the correlation maps, not an independent microscopic mechanism. The authors should state the identity ∆E = Jz explicitly and reframe Fig. 8 accordingly (e.g., as an equivalent diagnostic of the same control parameter), or demonstrate what Fig. 8 adds beyond Eq. (29). As written, the abstract's claim of a 'microscopic mechanism governing thermal quantum correlations' overstates what is shown.
  2. [§4, Eq. (37), Eq. (35)] The printed density-matrix elements are dimensionally inconsistent and must be corrected. η± contains 'χcosh(χ/2T³) ∓ 2hT² sinh(χ/2T³)' and γ contains '−T²(Jx+iJDM)... sinh(χ/2T³)': the hyperbolic arguments should be χ/2T and the stray powers T², T³ violate dimensional consistency (kB=1, h, χ, J all energies). Direct exponentiation of the 2×2 block in Eq. (33) gives η± = e^{Jz/4T}[cosh(χ/2T) ∓ (2h/χ)sinh(χ/2T)] and γ = −e^{Jz/4T}(Jx+iJDM)/χ sinh(χ/2T). This appears typographical, but it sits in the paper's central analytic result (Eq. (37)) and would mislead anyone reproducing the calculation. Similarly the definitions of a± and b after Eq. (35) should be typeset unambiguously (a± = (cosφ+cos(α/2))e^{±iα/2}).
  3. [§4, Eqs. (25)–(29); Figs. 2–7] The entire analysis is the canonical Gibbs state of the projected two-spin Hamiltonian (28)–(29), which is valid only in the weak-tunneling (Γ ≪ |ε|, ∆), large-U, singly-occupied regime of Ref. [19], with J ≈ Γ²/|ε|. Nowhere do Figs. 2–7 state energy units for J and T, and the maps are physically meaningful only if T is understood in units of J with T ≲ J ≪ |ε|, ∆ so the projection remains valid. The paper should (i) state the units of J and T explicitly on every figure axis, and (ii) add a short paragraph delimiting the parameter window in which the effective model, and hence the thermal maps, describes real devices. This is a correctness-risk issue for the device-level interpretation, not merely a presentation point: the abstract's conclusions about 'hybrid superconducting quantum devices' depend on it.
minor comments (6)
  1. [§5; Conclusion] The ordering LQFI ≥ LQU is a theorem (Eq. (18)), so presenting it as an empirical 'finding' ('LQFI remains consistently larger than LQU') is an overstatement; better framed as a consistency check of the numerics against the known inequality.
  2. [Keywords; §4] Typos: 'unceratainty' (keywords); 'one-site Coulomb repulsion' should read 'on-site' (§4); 'an state' before Eq. (24); 'monotonous dependence' should be 'non-monotonous' if that is intended (§4); 'dependance' (§4).
  3. [References] Reference duplication: [33] and [47] are the same paper; [38] and [46] are the same paper. Consolidate.
  4. [§3, Eqs. (20), (24)] Eqs. (20) and (24) introduce unitary-evolved-state generalizations of the hierarchy that are never used in the analysis; consider cutting or motivating them.
  5. [§4, Eq. (35)] The eigenvector normalization in Eq. (35) (|ψ0⟩, |ψ2⟩) would benefit from explicit closed forms of a± and b in terms of (J, φ, α) so the X-state construction is fully self-contained.
  6. [§5] No comparison with an entanglement measure (e.g., concurrence) is given; one line situating LQFI/LQU relative to entanglement for this X-state would help readers assess what 'quantum correlations beyond entanglement' means quantitatively here.

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity: standard LQFI/LQU applied to the Gibbs state of a cited effective Hamiltonian; parameters are scanned, not fitted.

full rationale

The derivation chain is self-contained and non-circular. The effective two-spin Hamiltonian (28)–(29) is taken from Spethmann et al. (external citation [19]); the thermal state (36)–(37) is the ordinary Gibbs state of that Hamiltonian; LQFI and LQU are evaluated from the textbook definitions (9)–(10) and (14)–(15). Temperature, tunneling J, phase φ, and spin–orbit angle α are free scan parameters, not fitted to recover a target correlation. The hierarchy LQFI ≥ LQU is checked against known inequalities (17)–(18), not forced by a normalization choice. Self-citations to Ohanyan’s prior dimer/entanglement work [50–67] are comparative background and do not underwrite the central claims. The observation that correlations track the ground–first-excited gap is ordinary thermal physics (Boltzmann suppression of excited states); even though the model identity χ = Jz makes ∆E = Jz, that is an internal spectral fact of the Hamiltonian, not a prediction that equals its input by construction. No fitted-input-as-prediction, uniqueness-from-authors, or ansatz-smuggling steps appear.

Assumptions & free parameters 4 free parameters · 5 assumptions · 0 invented entities

Central claims rest on (i) the effective Andreev dimer Hamiltonian imported from prior condensed-matter work, (ii) thermal equilibrium at inverse temperature β, and (iii) textbook LQFI/LQU formulas for qubits. No new particles or forces. Scan parameters J, α, φ, T are free knobs, not fits to experiment.

free parameters (4)
  • Effective exchange scale J = scanned; example J=0.5 in several figures
    Overall energy unit set by tunneling; scanned (e.g. J=0.5) rather than fixed from a microscopic device stack. Absolute correlation values depend on J/T.
  • Spin–orbit angle α = scanned; examples α=π/8
    Parameterizes SOI unitary; chosen by hand in plots (π/8, or scanned). Controls DM and exchange anisotropy.
  • Superconducting phase difference φ = scanned; fixed examples φ=π/8 or π
    External control parameter scanned over a period; not fitted.
  • Temperature T (kB=1) = scanned; examples T=0.1
    Thermal bath parameter in units of J; scanned to show decoherence of correlations.
assumptions (5)
  • domain assumption System is described by the effective Hamiltonian (28)–(29) derived under large on-site Coulomb repulsion, negative detuning, weak tunneling, and SOI unitary U=exp(iα u·S).
    Section 4 imports this from Spethmann et al.; all correlation results are properties of this H only.
  • domain assumption The two-qubit state is the Gibbs state ρ=e^{-βH}/Z at thermal equilibrium.
    Eq. (36); no driven or non-equilibrium dynamics.
  • standard math LQFI = 1−λmax(M) and LQU = 1−λmax(W) with M,W built from Pauli operators on one qubit as in Kim et al. / Girolami et al.
    Sections 2–3; standard qubit formulas.
  • standard math kB=1 and local observables are traceless normalized qubit Hamiltonians HA=σ·r.
    Conventional units and normalization for LQFI/LQU comparison.
  • domain assumption Microscopic gap, tunnel amplitudes, and detuning enter only through renormalized J≈Γ²/|ϵ| and the angles φ, α.
    Stated in Section 4 after Eq. (29); justifies scanning only effective parameters.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Thermal Quantum Correlations in Coupled Andreev Spin Qubits: Interplay of Superconducting Phase and Spin-Orbit Interaction." pith.science (2026). https://pith.science/paper/IZ73A4L5

@misc{pith2026260724521,
  author       = {Pith},
  title        = {Pith review of: Thermal Quantum Correlations in Coupled Andreev Spin Qubits: Interplay of Superconducting Phase and Spin-Orbit Interaction},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/IZ73A4L5}},
  note         = {Machine review of arXiv:2607.24521}
}
read the original abstract

We investigate thermal quantum correlations in a system of two coupled superconducting spin qubits described by an effective Andreev spin-qubit Hamiltonian in the presence of spin-orbit interaction. Using Local Quantum Fisher Information (LQFI) and Local Quantum Uncertainty (LQU) as quantum-correlation quantifiers, we analyze the effects of the superconducting phase difference, tunneling amplitude, spin-orbit coupling, and temperature on the nonclassical properties of the system. Analytical expressions for the thermal density matrix are obtained and employed to evaluate both quantities. Our results show that quantum correlations decrease monotonically with increasing temperature, while stronger tunneling and spin-orbit interaction significantly enhance their robustness. Moreover, the superconducting phase introduces a pronounced periodic behavior through the modulation of the effective exchange couplings, leading to constructive and destructive interference regimes that strongly influence the correlations. By analyzing the energy spectrum of the effective Hamiltonian, we demonstrate that the enhancement of quantum correlations is closely associated with an increased energy gap between the ground and first excited states, which suppresses thermal excitations and stabilizes the correlated ground state. Furthermore, LQFI is consistently larger than LQU throughout the investigated parameter space, reflecting its higher sensitivity to quantum fluctuations and local parameter estimation. These findings reveal the microscopic mechanism governing thermal quantum correlations in Andreev spin qubits and highlight the important roles of phase engineering, spin-orbit interaction, and tunneling in protecting quantum resources in hybrid superconducting quantum devices.

Figures

Figures reproduced from arXiv: 2607.24521 by the authors.

Figure 1
Figure 1. Schematic illustration of two coupled superconducting spin qubits formed by spin-1/2 quantum dots connected to superconducting leads SL and SR with phases ϕL and ϕR. The tunneling amplitudes between the quantum dots and the superconducting leads are denoted by tjn. Due to the presence of spin–orbit interaction (SOI), the tunneling processes become spin dependent and may involve spin-flip transitions. The superconduc… view at source ↗
Figure 2
Figure 2. (a) Local quantum Fisher information (LQFI) and (b) local quantum uncertainty (LQU) versus T and J for α = φ = π/8 [PITH_FULL_IMAGE:figures/full_fig_p014_2.png] view at source ↗
Figure 3
Figure 3. (a) Local quantum Fisher information (LQFI) and (b) local quantum uncertainty (LQU) versus φ and T for α = π/8 and J = 0.5 [PITH_FULL_IMAGE:figures/full_fig_p014_3.png] view at source ↗
Figures from the paper (5 more)
Figure 4
Figure 4. Figure 4: (a) Local quantum Fisher information (LQFI) and (b) local quantum uncertainty (LQU) versus φ and α for J = 0.5 and T = 0.1 [PITH_FULL_IMAGE:figures/full_fig_p015_4.png]
Figure 5
Figure 5. Figure 5: (a) Local quantum Fisher information (LQFI) and (b) local quantum uncertainty (LQU) versus α and T for φ = π and J = 0.5 [PITH_FULL_IMAGE:figures/full_fig_p015_5.png]
Figure 6
Figure 6. Figure 6: (a) Local quantum Fisher information (LQFI) and (b) local quantum uncertainty (LQU) versus φ and J for α = π/8 and T = 0.1 [PITH_FULL_IMAGE:figures/full_fig_p015_6.png]
Figure 7
Figure 7. Figure 7: (a) Local quantum Fisher information (LQFI) and (b) local quantum uncertainty (LQU) versus α and J for φ = π and T = 0.1. To further clarify the physical origin of the behavior of quantum correlations, [PITH_FULL_IMAGE:figures/full_fig_p016_7.png]
Figure 8
Figure 8. Figure 8: Energy spectrum of the effective Hamiltonian. The upper panels show the ground-state energy E0 and the first excited-state energy E1 as functions of (a) the superconducting phase difference φ for α = π/8 and J = 0.5, (b) the spin–orbit interaction strength α for φ = π …

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

67 extracted references · 17 canonical work pages

  1. [19]

    & Loss, D

    Spethmann, M., Zhang, X.-P., Klinovaja, J. & Loss, D. Coupled superconducting spin qubits with spin-orbit interaction.Physical Review B106(2022). URLhttp://dx.doi.org/10. 1103/PhysRevB.106.115411. Thermal Quantum Correlations in Coupled Andreev Spin Qubits: Interplay of Superconducting Phase and Spin–Orbit Interaction20

  2. [1]

    Nielsen, M. A. & Chuang, I. L.Quantum Computation and Quantum Information(Cambridge University Press, 2000)

  3. [2]

    Quantum computing in the nisq era and beyond.Quantum2, 79 (2018)

    Preskill, J. Quantum computing in the nisq era and beyond.Quantum2, 79 (2018). URL http://dx.doi.org/10.22331/q-2018-08-06-79

  4. [3]

    Bennett, C. H. & Brassard, G. Quantum cryptography: Public key distribution and coin tossing. Theoretical Computer Science560, 7–11 (2014). URLhttp://dx.doi.org/10.1016/j.tcs. 2014.05.025

  5. [4]

    URLhttp: //dx.doi.org/10.1038/nature23474

    Biamonte, J.et al.Quantum machine learning.Nature549, 195–202 (2017). URLhttp: //dx.doi.org/10.1038/nature23474

  6. [5]

    & Petruccione, F

    Schuld, M., Sinayskiy, I. & Petruccione, F. An introduction to quantum machine learning. Contemporary Physics56, 172–185 (2014). URLhttp://dx.doi.org/10.1080/00107514. 2014.964942

  7. [6]

    Algorithms for quantum computation: discrete logarithms and factoring

    Shor, P. Algorithms for quantum computation: discrete logarithms and factoring. InProceedings 35th Annual Symposium on Foundations of Computer Science, 124–134 (1994)

  8. [7]

    Grover, L. K. Quantum computers can search rapidly by using almost any transformation. Physical Review Letters80, 4329–4332 (1998). URLhttp://dx.doi.org/10.1103/ PhysRevLett.80.4329

Show all 67 references
  1. [8]

    & DiVincenzo, D

    Loss, D. & DiVincenzo, D. P. Quantum computation with quantum dots.Physical Review A57, 120–126 (1998). URLhttp://dx.doi.org/10.1103/PhysRevA.57.120

  2. [9]

    & Zhu, X

    Huang, H.-L., Wu, D., Fan, D. & Zhu, X. Superconducting quantum computing: a review.Science China Information Sciences63(2020). URLhttp://dx.doi.org/10.1007/ s11432-020-2881-9

  3. [10]

    URLhttp://dx.doi.org/10.1146/ annurev-conmatphys-031119-050605

    Kjaergaard, M.et al.Superconducting qubits: Current state of play.Annual Re- view of Condensed Matter Physics11(2020). URLhttp://dx.doi.org/10.1146/ annurev-conmatphys-031119-050605

  4. [11]

    H., Wallraff, A

    Devoret, M. H., Wallraff, A. & Martinis, J. M. Superconducting qubits: A short review (2004). URLhttps://arxiv.org/abs/cond-mat/0411174.cond-mat/0411174

  5. [12]

    Harvey, S. P. Quantum dots/spin qubits (2022). URLhttp://dx.doi.org/10.1093/acrefore/ 9780190871994.013.83

  6. [13]

    & Loss, D

    Kloeffel, C. & Loss, D. Prospects for spin-based quantum computing in quantum dots.Annual Review of Condensed Matter Physics4, 51–81 (2013). URLhttp://dx.doi.org/10.1146/ annurev-conmatphys-030212-184248

  7. [14]

    & Petta, J

    Awschalom, D., Bassett, L., Dzurak, A., Hu, E. & Petta, J. Quantum spintronics: Engineering and manipulating atom-like spins in semiconductors.Science (New York, N.Y.)339, 1174–9 (2013)

  8. [15]

    URLhttp://dx.doi.org/10.1038/nnano.2014.216

    Veldhorst, M.et al.An addressable quantum dot qubit with fault-tolerant control-fidelity.Nature Nanotechnology9, 981–985 (2014). URLhttp://dx.doi.org/10.1038/nnano.2014.216

  9. [16]

    URLhttp://dx.doi.org/10.1140/epjqt/ s40507-019-0072-0

    Krinner, S.et al.Engineering cryogenic setups for 100-qubit scale superconducting circuit systems.EPJ Quantum Technology6(2019). URLhttp://dx.doi.org/10.1140/epjqt/ s40507-019-0072-0

  10. [17]

    & Shukrinov, Y

    Pourkarimi, M., Haddadi, S., Nashaat, M., Kulikov, K. & Shukrinov, Y. Thermal local quantum uncertainty in a two-qubit-superconducting system under decoherence.Alexandria Engineering Journal83, 27–34 (2023). URLhttps://www.sciencedirect.com/science/article/pii/ S1110016823009377

  11. [18]

    Chtchelkatchev, N. M. & Nazarov, Y. V. Andreev quantum dots for spin manipulation.Physical Review Letters90(2003). URLhttp://dx.doi.org/10.1103/PhysRevLett.90.226806

  12. [20]

    Sauls, J. A. Andreev bound states and their signatures.Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences376, 20180140 (2018). URL http://dx.doi.org/10.1098/rsta.2018.0140

  13. [21]

    URLhttp://dx.doi.org/10.1126/science.abf0345

    Hays, M.et al.Coherent manipulation of an andreev spin qubit.Science373, 430–433 (2021). URLhttp://dx.doi.org/10.1126/science.abf0345

  14. [22]

    & Loss, D

    Choi, M.-S., Bruder, C. & Loss, D. Spin-dependent josephson current through double quantum dots and measurement of entangled electron states.Physical Review B62, 13569–13572 (2000). URLhttp://dx.doi.org/10.1103/PhysRevB.62.13569

  15. [23]

    Shor, P. W. Quantum computing.Documenta MathematicaExtra V olume ICM, 467–486 (1998). URLhttp://www.mathunion.org/ICM/ICM1998.3/Main/icm1998.3.0467.0486.ocr. pdf

  16. [24]

    & Pirandola, S

    Harney, C. & Pirandola, S. Secure quantum pattern communication.PRX Quantum3, 010311 (2022). URLhttps://link.aps.org/doi/10.1103/PRXQuantum.3.010311

  17. [25]

    & Maccone, L

    Giovannetti, V., Lloyd, S. & Maccone, L. Quantum-enhanced measurements: Beating the standard quantum limit.Science306, 1330–1336 (2004). URLhttp://dx.doi.org/10.1126/science. 1104149

  18. [26]

    Monemi, M.et al.Quantum integrated sensing and communication: Foundations, applications, and future directions (2026)

  19. [27]

    & Zurek, W

    Ollivier, H. & Zurek, W. H. Quantum discord: A measure of the quantumness of correlations. Physical Review Letters88(2001). URLhttp://dx.doi.org/10.1103/PhysRevLett.88. 017901

  20. [28]

    & Vedral, V

    Henderson, L. & Vedral, V. Classical, quantum and total correlations.Journal of Physics A: Mathematical and General34, 6899–6905 (2001). URLhttp://dx.doi.org/10.1088/ 0305-4470/34/35/315

  21. [29]

    Classical correlations and entanglement in quantum measurements.Phys

    Vedral, V. Classical correlations and entanglement in quantum measurements.Phys. Rev. Lett. 90, 050401 (2003). URLhttps://link.aps.org/doi/10.1103/PhysRevLett.90.050401

  22. [30]

    & Adesso, G

    Girolami, D., Tufarelli, T. & Adesso, G. Characterizing nonclassical correlations via local quantum uncertainty.Phys. Rev. Lett.110, 240402 (2013). URLhttps://link.aps.org/doi/10.1103/ PhysRevLett.110.240402

  23. [31]

    Werlang, T., Souza, S., Fanchini, F. F. & Villas Boas, C. J. Robustness of quantum discord to sudden death.Phys. Rev. A80, 024103 (2009). URLhttps://link.aps.org/doi/10.1103/ PhysRevA.80.024103

  24. [32]

    Bera, M. N. Role of quantum correlation in metrology beyond standard quantum limit (2014). URLhttps://arxiv.org/abs/1405.5357.1405.5357

  25. [33]

    Kim, S., Li, L., Kumar, A. & Wu, J. Characterizing nonclassical correlations via local quantum fisher information.Physical Review A97(2018). URLhttp://dx.doi.org/10. 1103/PhysRevA.97.032326

  26. [34]

    S., Bera, M

    Dhar, H. S., Bera, M. N. & Adesso, G. Characterizing non-markovianity via quantum interferometric power.Physical Review A91(2015). URLhttp://dx.doi.org/10.1103/ PhysRevA.91.032115

  27. [35]

    Physical Review Letters112(2014)

    Girolami, D.et al.Quantum discord determines the interferometric power of quantum states. Physical Review Letters112(2014). URLhttp://dx.doi.org/10.1103/PhysRevLett.112. 210401

  28. [36]

    Wigner, E. P. & Yanase, M. M. Information contents of distributions.Proceedings of the National Academy of Science49(1963). URLhttps://doi.org/10.1073/pnas.49.6.910

  29. [37]

    & Chandrasekar, V

    Muthuganesan, R. & Chandrasekar, V. K. Quantum fisher information and skew information correlations in dipolar spin system.Physica Scripta96, 125113 (2021). URLhttp://dx.doi. org/10.1088/1402-4896/ac2eca

  30. [38]

    & Ahl Laamara, R

    Slaoui, A., Bakmou, L., Daoud, M. & Ahl Laamara, R. A comparative study of local quantum fisher information and local quantum uncertainty in heisenberg xy model.Physics Letters A 383, 2241–2247 (2019). URLhttp://dx.doi.org/10.1016/j.physleta.2019.04.040. Thermal Quantum Correl...

  31. [39]

    Mohamed, A.-B. A. & Eleuch, H. Thermal local fisher information and quantum uncertainty in heisenberg model.Physica Scripta97, 095105 (2022). URLhttps://doi.org/10.1088/ 1402-4896/ac88ff

  32. [40]

    Yurischev, M. A. & Haddadi, S. Local quantum fisher information and local quantum uncertainty for general x states.Physics Letters A476, 128868 (2023). URLhttp://dx.doi.org/10. 1016/j.physleta.2023.128868

  33. [41]

    & Mansour, M

    Elghaayda, S., Dahbi, Z. & Mansour, M. Local quantum uncertainty and local quantum fisher information in two-coupled double quantum dots.Optical and Quantum Electronics54, 419 (2022). URLhttps://doi.org/10.1007/s11082-022-03829-y. Received: 1 February 2022; Accepted: 30 April ...

  34. [42]

    Benabdallah, F., Anouz, K. E. & Daoud, M. Toward the relationship between local quantum Fisher information and local quantum uncertainty in the presence of intrinsic decoherence.European Physical Journal Plus137, 548 (2022)

  35. [43]

    & Daoud, M

    El Bakraoui, M., Slaoui, A., El Hadfi, H. & Daoud, M. Enhancing the estimation precision of an unknown phase shift in multipartite glauber coherent states via skew information correlations and local quantum fisher information.Journal of the Optical Society of America B39, 1297...

  36. [44]

    Paris, M. G. Quantum estimation for quantum technology.International Journal of Quantum Information7, 125–137 (2009)

  37. [45]

    Braunstein, S. L. & Caves, C. M. Statistical distance and the geometry of quantum states.Physical Review Letters72, 3439 (1994)

  38. [46]

    & Laamara, R

    Slaoui, A., Bakmou, L., Daoud, M. & Laamara, R. A. A comparative study of local quantum fisher information and local quantum uncertainty in heisenberg xy model.Physics Letters A 383, 2241–2247 (2019)

  39. [47]

    Kim, S., Li, L., Kumar, A. & Wu, J. Characterizing nonclassical correlations via local quantum fisher information.Physical Review A97, 032326 (2018)

  40. [48]

    Wigner, E. P. & Yanase, M. M. Information contents of distributions.Proceedings of the National Academy of Sciences49, 910–918 (1963)

  41. [49]

    & Mu, Q.-X

    Guo, J.-L., Wei, J.-L., Qin, W. & Mu, Q.-X. Examining quantum correlations in the xy spin chain by local quantum uncertainty.Quantum Information Processing14, 1429–1442 (2015)

  42. [50]

    & Ohanyan, V

    Adamyan, Z., Muradyan, S. & Ohanyan, V. Quantum entanglement in spin dimers: Effects of a magnetic field and heterogeneous g-factors.Journal of Contemporary Physics (Armenian Academy of Sciences)55, 292–298 (2020)

  43. [51]

    & Bellucci, S

    Ohanyan, V., Rojas, O., Streˇ cka, J. & Bellucci, S. Absence of actual plateaus in zero-temperature magnetization curves of quantum spin clusters and chains.Phys. Rev. B92, 214423 (2015). URLhttps://link.aps.org/doi/10.1103/PhysRevB.92.214423

  44. [52]

    & Rojas, O

    Torrico, J., Rojas, M., de Souza, S. & Rojas, O. Zero temperature non-plateau magnetization and magnetocaloric effect in an ising-xyz diamond chain structure.Physics Letters A380, 3655–3660 (2016). URLhttps://www.sciencedirect.com/science/article/pii/S0375960116305308

  45. [53]

    http://www.w3.org/1998/math/mathml

    Adamyan, Z. & Ohanyan, V. Quantum entanglement in a mixed-spin trimer: Effects of a magnetic field and heterogeneous ¡mml:math xmlns:mml=“http://www.w3.org/1998/math/mathml”¿ ¡mml:mi¿g¡/mml:mi¿ ¡/mml:math¿ factors.Physical Review E110(2024). URLhttp: //dx.doi.org/10.1103/PhysR...

  46. [54]

    Adamyan, Z. Quantum entanglement in a mixed spin trimer (1/2,1/2,1) with non-conserved magnetization at finite temperatures.Journal of Contemporary Physics (Armenian Academy of Sciences)59, 279–286 (2025)

  47. [55]

    & Ohanyan, V

    Adamyan, Z. & Ohanyan, V. Tripartite entanglement in mixed-spin triangle trimmer.Condensed Matter Physics28, 33703 (2025).2409.01204

  48. [56]

    & Rojas, O

    Bellucci, S., Ohanyan, V. & Rojas, O. Magnetization non-rational quasi-plateau and spatially modulated spin order in the model of the single-chain magnet, [(CuL)2DyMo(CN)8]·2ch3cn·h2o. Europhysics Letters105, 47012 (2014). URLhttps://doi.org/10.1209/0295-5075/105/ Thermal Quan...

  49. [57]

    & Rojas, O

    Torrico, J., Ohanyan, V. & Rojas, O. Non-conserved magnetization operator and ‘fire-and-ice’ ground states in the ising-heisenberg diamond chain.Journal of Magnetism and Magnetic Materials454, 85–96 (2018). URLhttps://www.sciencedirect.com/science/article/pii/ S0304885317335400

  50. [58]

    & Honecker, A

    Ohanyan, V. & Honecker, A. Magnetothermal properties of the heisenberg-ising orthogonal- dimer chain with triangularxxzclusters.Phys. Rev. B86, 054412 (2012). URLhttps: //link.aps.org/doi/10.1103/PhysRevB.86.054412

  51. [59]

    Varizi, A. D. & Drumond, R. C. Quantum ising model in a period-2 modulated transverse field. Phys. Rev. E100, 022104 (2019). URLhttps://link.aps.org/doi/10.1103/PhysRevE.100. 022104

  52. [60]

    & Derzhko, O

    Krokhmalskii, T., Verkholyak, T., Baran, O., Ohanyan, V. & Derzhko, O. Spin- 1 2 xx chain in a transverse field with regularly alternatinggfactors: Static and dynamic properties.Phys. Rev. B102, 144403 (2020). URLhttps://link.aps.org/doi/10.1103/PhysRevB.102.144403

  53. [61]

    & Chitov, G

    Pandey, T. & Chitov, G. Y. Phase diagram and topological order in the modulated xyz chain with magnetic field.Phys. Rev. B102, 054436 (2020). URLhttps://link.aps.org/doi/10. 1103/PhysRevB.102.054436

  54. [62]

    & Brenig, W

    Metavitsiadis, A., Psaroudaki, C. & Brenig, W. Enhancement of magnetization plateaus in low- dimensional spin systems.Phys. Rev. B101, 235143 (2020). URLhttps://link.aps.org/ doi/10.1103/PhysRevB.101.235143

  55. [63]

    I., Cheraghi, H

    Japaridze, G. I., Cheraghi, H. & Mahdavifar, S. Magnetic phase diagram of a spin-1/2xxzchain with modulated dzyaloshinskii-moriya interaction.Phys. Rev. E104, 014134 (2021). URL https://link.aps.org/doi/10.1103/PhysRevE.104.014134

  56. [64]

    Magnetocaloric effect in the one-dimensional spin-1/2 xx model with two periodically varying g-factors.Ukrainian Journal of Physics68, 488 (2023)

    Baran, O. Magnetocaloric effect in the one-dimensional spin-1/2 xx model with two periodically varying g-factors.Ukrainian Journal of Physics68, 488 (2023)

  57. [65]

    Influence of xy anisotropy on a magnetoelectric effect in spin-1/2 xy chain in a transverse magnetic field.Condensed Matter Physics23, 43704 (2020)

    Ohanyan, V. Influence of xy anisotropy on a magnetoelectric effect in spin-1/2 xy chain in a transverse magnetic field.Condensed Matter Physics23, 43704 (2020). URLhttp: //dx.doi.org/10.5488/CMP.23.43704

  58. [66]

    Yin, W., Roth, C. R. & Tsvelik, A. M. Spin frustration and an exotic critical point in ferromagnets from nonuniform oppositegfactors.Phys. Rev. B109, 054427 (2024). URL https://link.aps.org/doi/10.1103/PhysRevB.109.054427

  59. [67]

    & Tsvelik, A

    Yin, W. & Tsvelik, A. M. Phase switch driven by the hidden half-ice, half-fire state in a ferrimagnet.Phys. Rev. Lett.133, 266701 (2024). URLhttps://link.aps.org/doi/10.1103/ PhysRevLett.133.266701. Acknowledgements V.O. expresses his gratitude to CS RA MESCS for partial finan...

Pith tools

Reviewed July 31, 2026 · model on record in the stance chip above.