Palacký University
Controlling the state of motion of optically levitated nanoparticles is crucial for the advancement of precision sensing, fundamental tests of physics, and the development of hybrid classical-quantum technologies. Experimentally, such control can be achieved by pulsed modifications of the optical potential confining the nanoparticle. Most frequently, the applied potential pulses are parabolic in nanoparticle position, and they expand/squeeze or displace the initial Gaussian state of motion to a modified Gaussian state. The time-dependent mean values and covariance matrix of the phase-space variables can fully characterize such a state. However, quasi-parabolic optical potentials with added weak Duffing-type nonlinearity, encountered in real-world experiments, can generally distort the state of motion to a non-Gaussian one, for which the description based solely on the mean values and covariance matrix fails. Here, we introduce a nonlinear transformation of the phase-space coordinates using the concept of Fermat's spiral, which effectively removes the state distortion induced by the Duffing-type nonlinearity and enables characterization of the state of motion by the standard Gaussian-state metrics. Comparisons of the experimental data with theoretical models show that the proposed coordinate transformation can recover the ideal behavior of a harmonic oscillator even after extended evolution of the system in the nonlinear potential. The presented scheme enables the separation of the effects of the applied state manipulation, the system's gradual thermalization, and the nonlinearity of the confinement on the experimentally observed dynamics of the system, thereby facilitating the design of advanced protocols for levitated optomechanics.
29 Apr 2012
An observable on a quantum structure is any σ\sigma-homomorphism of quantum structures from the Borel σ\sigma-algebra into the quantum structure. We show that our partial information on an observable known only for all intervals of the form (,t)(-\infty,t) is sufficient to determine uniquely the whole observable defined on quantum structures like σ\sigma-MV-algebras, σ\sigma-effect algebras, Boolean σ\sigma-algebras, monotone σ\sigma-complete effect algebras with the Riesz Decomposition Property, the effect algebra of effect operators of a Hilbert space, and a system of functions, and an effect-tribe.
We present a universal deep-learning method that reconstructs super-resolved images of quantum emitters from a single camera frame measurement. Trained on physics-based synthetic data spanning diverse point-spread functions, aberrations, and noise, the network generalizes across experimental conditions without system-specific retraining. We validate the approach on low- and high-density In(Ga)As quantum dots and strain-induced dots in 2D monolayer WSe2_2, resolving overlapping emitters even under low signal-to-noise and inhomogeneous backgrounds. By eliminating calibration and iterative acquisitions, this single-shot strategy enables rapid, robust super-resolution for nanoscale characterization and quantum photonic device fabrication.
Direct measurement of quantum non-Gaussianity requires some variant of a discrete photon-resolving detection, which is feasible only for low mean photon numbers. For a large mean photon number, intensity detection by linear photodiodes provides a continuous signal; therefore, the Fock probabilities of the unknown input state are not directly available. On the other hand, intensity moments can be measured directly, and photon-number moments can be estimated. Therefore, we derive and analyze a quantum non-Gaussianity witness based solely on the photon number mean and variance (or alternatively, the second-order correlation g(2)g^{(2)}) of an unknown state. Due to the simplicity of the used photon-number moments, the measurement results are easy to correct for losses and additive noise. We provide examples of simple amplification-based measurement schemes where our witness can be applied directly, thereby opening pathways to proof-of-principle tests and applications.
CNRS logoCNRSUniversity of New South WalesINFN Sezione di NapoliMonash University logoMonash UniversityUniversity of Manchester logoUniversity of ManchesterUniversity of Chicago logoUniversity of ChicagoUniversity of Oxford logoUniversity of Oxfordthe University of Tokyo logothe University of TokyoNagoya University logoNagoya UniversityKyoto University logoKyoto UniversityETH Zürich logoETH ZürichRIKEN logoRIKENUniversidade de LisboaINFN Sezione di PisaUniversity of InnsbruckWeizmann Institute of ScienceUniversité Paris-Saclay logoUniversité Paris-SaclayFriedrich-Alexander-Universität Erlangen-NürnbergSorbonne Université logoSorbonne UniversitéInstitut Polytechnique de ParisMacquarie UniversityCEA logoCEAUniversity of GenevaDublin City UniversityHumboldt-Universität zu BerlinUniversitat de BarcelonaUniversidade Federal do ABCHigh Energy Accelerator Research Organization (KEK)University of LeicesterUniversity of DelawareUniversidad Complutense de MadridNicolaus Copernicus Astronomical Center, Polish Academy of SciencesObservatoire de ParisHiroshima UniversityUniversity of JohannesburgNational Institute of Technology, DurgapurUniversidad Nacional Autónoma de MéxicoJagiellonian UniversityInstituto de Astrofísica de CanariasGran Sasso Science Institute (GSSI)Universidad de ChileUniversidade de São PauloUniversität HamburgRuđer Bošković InstituteWaseda University logoWaseda UniversityUniversity of AdelaideUniversitat Autònoma de BarcelonaCNESINFN, Sezione di TorinoPontificia Universidad Católica de ChileUniversidade Federal de Santa CatarinaTechnische Universität DortmundPSL Research UniversityUniversidad de La LagunaUniversity of Hawaii at ManoaJosip Juraj Strossmayer University of OsijekUniversità degli Studi di SienaMax-Planck-Institut für PhysikINAF – Istituto di Astrofisica Spaziale e Fisica Cosmica MilanoLaboratoire d’Astrophysique de MarseilleINFN Sezione di PerugiaINAF-Istituto di RadioastronomiaInstituto de Astrofísica de Andalucía, IAA-CSICINAF – Osservatorio Astronomico di RomaWestern Sydney UniversityLAPPFZU - Institute of Physics of the Czech Academy of SciencesINFN - Sezione di PadovaKumamoto UniversityIJCLabNational Academy of Sciences of UkraineUniversity of DurhamINAF- Osservatorio Astronomico di CagliariUniversity of NamibiaKing Mongkut’s Institute of Technology LadkrabangUniversidad de GuadalajaraUniversidade Presbiteriana MackenzieLaboratoire Univers et Particules de MontpellierLaboratoire Leprince-RinguetPalacký UniversityCentro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT)INFN, Sezione di CataniaINFN Sezione di RomaLPNHEYerevan Physics InstituteINFN Sezione di Roma Tor VergataAIMIFAEKavli Institute for the Physics and Mathematics of the Universe (WPI),Universidad Metropolitana de Ciencias de la EducaciónUniversità degli Studi di Bari Aldo MoroInstitut de Ciències del Cosmos (ICCUB)Centro Brasileiro de Pesquisas Físicas - CBPFAstroparticule et Cosmologie (APC)Open University of IsraelAstronomical Institute, Czech Academy of SciencesInstituto de Física de Partículas y del Cosmos IPARCOSInstituto de Física de São CarlosIEEC-UBLaboratoire APCINFN (Sezione di Bari)University of WitswatersrandCentre d'Etudes Nucléaires de Bordeaux GradignanINFN Sezione di UdineMPI für Kernphysik* North–West UniversityINFN-Sezione di Roma TreUniversit de ParisINAF Osservatorio Astronomico di CapodimonteMax Planck Institut fr AstronomieAix-Marseille Universit",Universit de BordeauxUniversit Savoie Mont BlancUniversit Paris CitINAF Osservatorio Astrofisico di ArcetriUniversit de MontpellierUniversit degli Studi di TorinoTechnion Israel Institute of Technologycole Polytechnique
Galaxy clusters are expected to be dark matter (DM) reservoirs and storage rooms for the cosmic-ray protons (CRp) that accumulate along the cluster's formation history. Accordingly, they are excellent targets to search for signals of DM annihilation and decay at gamma-ray energies and are predicted to be sources of large-scale gamma-ray emission due to hadronic interactions in the intracluster medium. We estimate the sensitivity of the Cherenkov Telescope Array (CTA) to detect diffuse gamma-ray emission from the Perseus galaxy cluster. We perform a detailed spatial and spectral modelling of the expected signal for the DM and the CRp components. For each, we compute the expected CTA sensitivity. The observing strategy of Perseus is also discussed. In the absence of a diffuse signal (non-detection), CTA should constrain the CRp to thermal energy ratio within the radius R500R_{500} down to about $X_{500}<3\times 10^{-3}$, for a spatial CRp distribution that follows the thermal gas and a CRp spectral index αCRp=2.3\alpha_{\rm CRp}=2.3. Under the optimistic assumption of a pure hadronic origin of the Perseus radio mini-halo and depending on the assumed magnetic field profile, CTA should measure αCRp\alpha_{\rm CRp} down to about ΔαCRp0.1\Delta\alpha_{\rm CRp}\simeq 0.1 and the CRp spatial distribution with 10% precision. Regarding DM, CTA should improve the current ground-based gamma-ray DM limits from clusters observations on the velocity-averaged annihilation cross-section by a factor of up to 5\sim 5, depending on the modelling of DM halo substructure. In the case of decay of DM particles, CTA will explore a new region of the parameter space, reaching models with \tau_{\chi}&gt;10^{27}s for DM masses above 1 TeV. These constraints will provide unprecedented sensitivity to the physics of both CRp acceleration and transport at cluster scale and to TeV DM particle models, especially in the decay scenario.
Randomness is a key feature of quantum physics. Heisenberg's uncertainty principle reveals existence of an intrinsic noise, usually explored through Gaussian squeezed states. Due to their insufficiency for quantum advantage, the focus is currently shifting towards genuinely quantum non-Gaussian states. However, while the genuine quantum behavior comes naturally to discrete variable systems, its preparation and verification is difficult in the continuous ones. Simultaneously, a unifying theoretical framework based on the continuous nature is missing. Here, we introduce nonlinear squeezing as a general framework to describe and verify genuine quantumness in noise of continuous quantum states. Using this approach, we certify the non-Gaussianity of experimentally prepared multi-photon-added coherent states of light for the first time. Chiefly, we demonstrated the nonlinear squeezing corresponding to third- and fifth-order quantum nonlinearities, going significantly beyond the current state-of-the-art in quantum technology. This framework advances quantum science and supports the development of quantum technologies by uncovering intricate quantum properties in cutting-edge experiments.
In deep-inelastic positron-proton scattering, the lepton-jet azimuthal angular asymmetry is measured using data collected with the H1 detector at HERA. When the average transverse momentum of the lepton-jet system, $\lvert \vec{P}_\perp \rvert $, is much larger than the total transverse momentum of the system, q\lvert \vec{q}_\perp \rvert, the asymmetry between parallel and antiparallel configurations, P\vec{P}_\perp and q\vec{q}_\perp, is expected to be generated by initial and final state soft gluon radiation and can be predicted using perturbation theory. Quantifying the angular properties of the asymmetry therefore provides an additional test of the strong force. Studying the asymmetry is important for future measurements of intrinsic asymmetries generated by the proton's constituents through Transverse Momentum Dependent (TMD) Parton Distribution Functions (PDFs), where this asymmetry constitutes a dominant background. Moments of the azimuthal asymmetries are measured using a machine learning method for unfolding that does not require binning.
An adaptive non-Gaussian measurement scheme is proposed for implementing a quantum cubic gate on a traveling light beam, utilizing one squeezed vacuum state and a non-Gaussian ancilla. The work demonstrates that classical adaptive control generates the gate's nonlinearity while the non-Gaussian ancilla suppresses noise, also identifying optimal photon-number superposition states to minimize this noise.
Recently Jenei introduced a new structure called equality algebras which is inspired by ideas of BCK-algebras with meet. These algebras were generalized by Jenei and Kóródi to pseudo equality algebras which are aimed to find a connection with pseudo BCK-algebras with meet. We show that every pseudo equality algebra is an equality algebra. Therefore, we define a new type of pseudo equality algebras which more precisely reflects the relation to pseudo BCK-algebras with meet in the sense of Kabziński and Wroński. We describe congruences via normal closed deductive systems, and we show that the variety of pseudo equality algebras is subtractive, congruence distributive and congruence permutable.
Superposed coherent states are central to quantum technologies, yet their reliable identification remains a challenge, especially in noisy or resource-constrained settings. We introduce a novel, directly measurable criterion for detecting cat-like features in quantum states, rooted in the concept of nonlinear squeezing. This approach bypasses the need for full state tomography and reveals structure where fidelity fails. The numerical results confirm its robustness under loss and its potential for experimental implementation. The method naturally generalizes to more exotic superpositions, including multiheaded cat states.
Peierls theorem postulates that a one-dimensional (1D) metallic chain must undergo a metal-to-insulator transition via lattice distortion, resulting in bond length alternation (BLA) within the chain. The validity of this theorem has been repeatedly proven in practice, as evidenced by the absence of a metallic phase in low-dimensional atomic lattices and electronic crystals, including conjugated polymers, artificial 1D quantum nanowires, and anisotropic inorganic crystals. Overcoming this transition enables realizing long-sought organic quantum phases of matter, including 1D synthetic organic metals and even high-temperature organic superconductors. Herein, we demonstrate that the Peierls transition can be globally suppressed by employing lattice topology engineering of classic trans-polyacetylene chains connected to open-shell nanographene terminals. The appropriate topology connection enables an effective interplay between the zero-energy modes (ZMs) of terminal and the finite odd-membered polyacetylene (OPA) chains. This creates a critical topology-defined highest occupied molecular orbital (HOMO) that compensates for bond density variations, thereby suppressing BLA and reestablishing their quasi-1D metallic character. Moreover, it also causes the formation of an unconventional boundary-free resonance state, being delocalized over the entire chain with non-decaying spectral weight, distinguishing them from traditional solitons observed in polyacetylene. Our finding sets the stage for pioneering the suppression of material instability and the creation of synthetic organic quantum materials with unconventional quantum phases previously prohibited by the Peierls transition.
We discuss how introducing an equilibrium frame, in which a given Hamiltonian has balanced loss and gain terms, can reveal PT symmetry hidden in non-Hermitian Hamiltonians of dissipative systems. Passive PT-symmetric Hamiltonians, in which only loss is present and gain is absent, can also display exceptional points, just like PT-symmetric systems, and therefore are extensively investigated. We demonstrate that non-Hermitian Hamiltonians, which can be divided into a PT-symmetric term and a term commuting with the Hamiltonian, possess hidden PT symmetries. These symmetries become apparent in the equilibrium frame. We also show that the number of eigenstates having the same value in an exceptional point is usually smaller in the initial frame than in the equilibrium frame. This property is associated with the second part of the Hamiltonian.
In response to increasing threats to biodiversity, conservation objectives have been set at national and international level, with the aim of halting biodiversity decline by reducing direct anthropogenic pressures on species. However, the potential effects of conservation policies derived from these objectives on common species remain rarely studied. Common species are often not the primary species targeted by conservation measures and can be distributed across a wide range of habitats that may be affected differently by these measures. We analyse the effect of a range of pressures related to climate, land use and land use intensity, on 263 common bird and 144 common butterfly species from more than 20,000 sites between 2000 and 2021 across 26 European countries. We use land-use and land-use-intensity change scenarios produced previously using the IPBES Nature Futures Framework to support the achievement of conservation objectives, as well as climate change scenarios in order to project the future of biodiversity pressures in Europe up to 2050. To project the future of common biodiversity in these scenarios, we translate these pressure changes into expected variations of abundances for all common bird and butterfly species, as well as for the multi-species indicators used to monitor common biodiversity status in Europe. The projected trends are improved, while still declining, for birds in particular farmland species under the scenarios that meet the conservation objectives, with few effects on butterflies. No scenario shows a stop or a reversal in the decline in abundance of bird and butterfly species that are currently common, on the time scale considered. Our results therefore call into question the fate of common biodiversity under the current conservation policies and the need for other anticipatory frameworks that do not implicitly require a growing need for natural resources.
Following [Botur, M., Chajda, I., Halaš, R.: Are basic algebras residuated structures?, Soft Comput. 14 (2010), 251-255] we discuss the connections between left-residuated partially ordered groupoids and the so-called basic algebras, which are a non-commutative and non-associative generalization of MV-algebras and orthomodular lattices.
Non-Hermitian systems have been at the center of intense research for over a decade, partly due to their nontrivial energy topology formed by intersecting Riemann manifolds with branch points known as exceptional points (EPs). This spectral property can be exploited, e.g., to achieve topologically controlled state permutations that are necessary for implementing a wide class of classical and quantum information protocols. However, the complex-valued spectra of typical non-Hermitian systems lead to instabilities, losses, and breakdown of adiabaticity, which impedes the practical use of EP-induced energy topologies in quantum information protocols based on state permutation symmetries. Indeed, in a given non-Hermitian multiqubit system, the dynamical winding around EPs always results in a predetermined set of attenuated final eigenstates, due to the interplay of decoherence and non-adiabatic transitions, irrespective of the initial conditions. In this work, we address this long-standing problem by introducing a model of interacting qubits governed by an effective non-Hermitian Hamiltonian that hosts novel types of EPs while maintaining a completely real energy spectrum, ensuring the absence of losses in the system's dynamics. We demonstrate that such non-Hermitian Hamiltonians enable the realization of genuine, in general, non-Abelian permutation groups in the multiqubit system's eigenspace while dynamically encircling these EPs. Our findings indicate that, contrary to previous beliefs, non-Hermiticity can be utilized to achieve controlled topological state permutations in time-modulated multiqubit systems, thus paving the way for the advancement and development of novel quantum information protocols in real-world non-Hermitian quantum systems.
National United UniversityCharles UniversityNational Central UniversityChinese Academy of Sciences logoChinese Academy of SciencesSichuan UniversitySun Yat-Sen University logoSun Yat-Sen UniversityUniversity of Science and Technology of China logoUniversity of Science and Technology of ChinaBeihang University logoBeihang UniversityNational Taiwan UniversityNanjing University logoNanjing UniversityTsinghua University logoTsinghua UniversityNankai UniversityJoint Institute for Nuclear ResearchJilin UniversityShandong University logoShandong UniversityXiangtan UniversitySoochow UniversityTechnische Universität MünchenUniversity of HamburgAix Marseille UniversityUniversità degli Studi di PaviaUniversity of JyväskyläUniversity of AlabamaINFN, Sezione di PaviaDongguan University of TechnologyUniversità degli Studi di BolognaXian Jiaotong UniversityINFN, Laboratori Nazionali di FrascatiEberhard-Karls-Universität TübingenNorth China Electric Power UniversityComenius UniversityINFN, Sezione di MilanoInstitute of high-energy PhysicsChina Institute of Atomic EnergyINFN - Sezione di PadovaUniversità degli Studi di CataniaInstitute for Nuclear Research, Russian Academy of SciencesKing Mongkut’s Institute of Technology LadkrabangPalacký UniversityParis-Saclay UniversityINFN, Sezione di CataniaINFN-Sezione di BolognaUniversitá dell’InsubriaUniversità degli Studi di Roma TreSkobeltsyn Institute of Nuclear Physics, Moscow State UniversityZhongshan UniversityDaya Bay Nuclear Power Joint LaboratoryLAPP, Université Savoie Mont Blanc, CNRS/IN2P3INFN-Sezione di Roma TreINFN-Sezione di FerraraUniversit degli Studi di GenovaUniversit degli Studi di PerugiaUniversit Libre de BruxellesUniversit degli Studi di PadovaNational Research Nuclear University ","MEPhIRWTH Aachen University
JUNO is a massive liquid scintillator detector with a primary scientific goal of determining the neutrino mass ordering by studying the oscillated anti-neutrino flux coming from two nuclear power plants at 53 km distance. The expected signal anti-neutrino interaction rate is only 60 counts per day, therefore a careful control of the background sources due to radioactivity is critical. In particular, natural radioactivity present in all materials and in the environment represents a serious issue that could impair the sensitivity of the experiment if appropriate countermeasures were not foreseen. In this paper we discuss the background reduction strategies undertaken by the JUNO collaboration to reduce at minimum the impact of natural radioactivity. We describe our efforts for an optimized experimental design, a careful material screening and accurate detector production handling, and a constant control of the expected results through a meticulous Monte Carlo simulation program. We show that all these actions should allow us to keep the background count rate safely below the target value of 10 Hz in the default fiducial volume, above an energy threshold of 0.7 MeV.
We introduce Riesz space-valued states, called (R,1R)(R,1_R)-states, on a pseudo MV-algebra, where RR is a Riesz space with a fixed strong unit 1R1_R. Pseudo MV-algebras are a non-commutative generalization of MV-algebras. Such a Riesz space-valued state is a generalization of usual states on MV-algebras. Any (R,1R)(R,1_R)-state is an additive mapping preserving a partial addition in pseudo MV-algebras. Besides we introduce (R,1R)(R,1_R)-state-morphisms and extremal (R,1R)(R,1_R)-states, and we study relations between them. We study metrical completion of unital \ell-groups with respect to an (R,1R)(R,1_R)-state. If the unital Riesz space is Dedekind complete, we study when the space of (R,1R)(R,1_R)-states is a Choquet simplex or even a Bauer simplex.
We present the generation of approximated coherent state superpositions - referred to as Schrödinger cat states - by the process of subtracting single photons from picosecond pulsed squeezed states of light at 830 nm. The squeezed vacuum states are produced by spontaneous parametric down-conversion (SPDC) in a periodically poled KTiOPO4 crystal while the single photons are probabilistically subtracted using a beamsplitter and a single photon detector. The resulting states are fully characterized with time-resolved homodyne quantum state tomography. Varying the pump power of the SPDC, we generated different states which exhibit non-Gaussian behavior.
We show that every pseudo hoop satisfies the Riesz Decomposition Property. We visualize basic pseudo hoops by functions on a linearly ordered set. Finally, we study normal-valued basic pseudo hoops giving a countable base of equations for them.
The paper deals with an algebraic extension of MVMV-algebras based on the definition of generalized Boolean algebras. We introduce a new algebraic structure, not necessarily with a top element, which is called an EMVEMV-algebra and every EMVEMV-algebra contains an MVMV-algebra. First, we present basic properties of EMVEMV-algebras, give some examples, introduce and investigate congruence relations, ideals and filters on this algebra. We show that each EMVEMV-algebra can be embedded into an MVMV-algebra and we characterize EMVEMV-algebras either as MVMV-algebras or maximal ideals of MVMV-algebras. We study the lattice of ideals of an EMVEMV-algebra and prove that any EMVEMV-algebra has at least one maximal ideal. We define an EMVEMV-clan of fuzzy sets as a special EMVEMV-algebra. We show any semisimple EMVEMV-algebra is isomorphic to an EMVEMV-clan of fuzzy functions on a set. We consider the variety of EMVEMV-algebra and we present an equational base for each proper subvariety of the variety of EMVEMV-algebras. We establish a categorical equivalencies of the category of proper EMVEMV-algebras, the category of MVMV-algebras with a fixed special maximal ideal, and a special category of Abelian unital \ell-groups.
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