Search
Filters
total: 1260
filtered: 761
-
Catalog
Chosen catalog filters
Search results for: QUANTUM METROLOGY
-
Quantum aspects of semantic analysis and symbolic artificial intelligence.
PublicationNowoczesne podejścia do analizy semantycznej, jeśli przeformułować je w język przestrzeni Hilberta, ujawniają formalne struktury znane z mechaniki kwantowej. Podobna sytuacja występuje w rozproszonych reprezentacjach struktur poznawczych rozwijanych na użytek sieci neuronowych. W pracy przyglądamy się różnicom i podobieństwom owych teorii do kwantowej teorii informacji.
-
Direct measurement of nonlinear properties of bipartite quantum states
PublicationNieliniowe własności stanów kwantowych, takie jak entropia, splątania, określają ilość ważnych fizycznych źródeł i są często używane w informatyce kwantowej. Na ogół są one obliczane z pełnego opisu stanu kwantowego, pomimo tego, że zależą od niewielkiej ilości parametrów opisujących dany stan. Wyciągamy nielokalną i nieliniową wielkość, mianowicie entropię Renyi, z lokalnych pomiarów dwóch par fotonów splątanych polaryzacyjnie.
-
Choroby kobiet i sposoby ich leczenia na podstawie traktatu Metrodory z Bizancjum
Publication -
Profesor Stanisław Trzetrzewiński pionierem metrologii na Politechnice Gdańskiej. - [przedruk nr rek: 128900]
PublicationW artykule przedstawiono życiorys i dorobek organizatora Katedry Miernictwa Elektrycznego Politechniki Gdańskiej - profesora Stanisława Trzetrzewińskiego. Stanisław Trzetrzewiński urodził się w 1901 r. w Kijowie. Ukończył Wydział Elektryczny Politechniki Warszawskiej w 1928 roku, w latach 1925-1934 pracował na tej uczelni jako asystent, następnie przeniósł się do Państwowych Zakładów Tele- i Radiotechnicznych w Warszawie. Równocześnie...
-
Metrozony - wewnątrzmetropolitalne obszary rozwojowe w kontekście rozwoju dzielnic przyportowych Hamburga i Gdańska
Publication.
-
Możliwości i ryzyka związane z automatyzacją weryfikacji pracy studentów na przykładzie przedmiotu Metrologia
PublicationPrzedmiot Metrologia jest wykładany na Wydziale Elektroniki, Telekomunikacji i Informatyki Politechniki Gdańskiej na trzecim semestrze studiów na trzech kierunkach: Elektronika i Telekomunikacja, Inżynieria Biomedyczna oraz Automatyka, Cybernetyka i Robotyka. W trakcie zajęć laboratoryjnych studenci wykonują sześć ćwiczeń, z których dwa są całkowicie oceniane przez program weryfikujący...
-
O działalności Komitetu Metrologii i Aparatury Naukowej Polskiej Akademii Nauk w roku 2002
PublicationPrzedstawiono skład osobowy oraz struktury działalności Komitetu Metrologii Aparatury Naukowej PAN. Opisano bardziej szczegółowo działalność naukową i organizacyjną, aktywność konferencyjną krajową i międzynarodową oraz aktywność wydawniczą w roku 2002.
-
Quantum strategies for rendezvous and domination tasks on graphs with mobile agents
PublicationThis paper explores the application of quantum nonlocality, a renowned and unique phenomenon acknowledged as a valuable resource. Focusing on an alternative application, we demonstrate its quantum advantage for mobile agents engaged in specific distributed tasks without communication. The research addresses the significant challenge of rendezvous on graphs and introduces a distributed task for mobile agents grounded in the graph...
-
Quantum states representing perfectly secure bits are always distillable
PublicationW pracy pokazano, że ostatnio wprowadzone stany kwantowe reprezentujące perfekcyjnie bezpieczny bit klucza kryptograficznegooraz ich wielocząstkowe i wielowymiarowe uogólnienia zawsze reprezentują destylowalne splątanie. Podano ograniczenia dolne na wielkość destylowalnego splątania. Ponadto podano alternatywny dowód faktu, że koszt splątania jest ograniczeniem górnym na wielkość destylowalnego klucza kryptograficznego w dwucząstkowym...
-
The optimized Rayleigh–Ritz scheme for determining the quantum-mechanical spectrum
Publication -
Correlation and Entanglement in Elliptically Deformed Two-Electron Quantum Dots
Publication -
On the distillation of cryptographic key from multipartie entangled quantum states
PublicationCelem pracy było uzupełnienie ogólnego paradygmatu destylacji bezpiecznego klucza kryptograficznego z dwucząstkowych stanów splątanych, a w szczegolności znalezienie nowych konstrukcji stanów kwantowych o splątaniu związanym z niezerowym destylowanym kluczem kryptograficznym. Kolejnym celem pracy było uogólnienie powyższego paradygmatu dwucząstkowego na przypadek wielu cząstek. W szczególności sformułowanie definicji wielocząstkowych...
-
The quantum free energy barrier for hydrogen vacancy diffusion in Na3AlH6
Publication -
Quantum chemical modelling of the process of lithium insertion into WO3 films
Publication -
Imitating Quantum Probabilities: Beyond Bell’s Theorem and Tsirelson Bounds
PublicationLocal hidden-variable model of singlet-state correlations discussed in M. Czachor, Acta Phys. Polon. A 139, 70, is shown to be a particular case of an infinite hierarchy of local hidden-variable models based on an infinite hierarchy of calculi. Violation of Bell-type inequalities can be interpreted as a `confusion of languages' problem, a result of mixing different but neighboring levels of the hierarchy. Mixing of non-neighboring...
-
Nuclear quantum effects in a HIV/cancer inhibitor: The case of ellipticine
Publication -
Spectroscopic and quantum chemical study of phthalocyanines with 1,4,7-trioxanonyl moieties
Publication -
Efficient bounds on quantum-communication rates via their reduced variants
PublicationWe investigate one-way communication scenarios where Bob operating on his component can transfer some subsystem to the environment. We define reduced versions of quantum-communication rates and, further, prove upper bounds on a one-way quantum secret key, distillable entanglement, and quantum-channel capacity by means of their reduced versions. It is shown that in some cases they drastically improve their estimation.
-
Quantum mechanical which-way experiment with an internal degree of freedom
PublicationFor a particle travelling through an interferometer, the trade-off between the available which-way information and the interference visibility provides a lucid manifestation of the quantum mechanical wave-particle duality. Here we analyse this relation for a particle possessing an internal degree of freedom such as spin. We quantify the trade-off with a general inequality that paints an unexpectedly intricate picture of wave-particle...
-
General paradigm for distilling classical key from quantum states
PublicationIn this paper, we develop a formalism for distilling aclassical key from a quantum state in a systematic way, expandingon our previous work on a secure key from bound entanglement(Horodecki et al., 2005). More detailed proofs, discussion, andexamples are provided of the main results. Namely, we demonstratethat all quantum cryptographic protocols can be recast in away which looks like entanglement theory, with the only changebeing...
-
Device-independent quantum key distribution based on measurement inputs
PublicationWe provide an analysis of a family of device-independent quantum key distribution (QKD) protocols that has the following features. (a) The bits used for the secret key do not come from the results of the measurements on an entangled state but from the choices of settings. (b) Instead of a single security parameter (a violation of some Bell inequality) a set of them is used to estimate the level of trust in the secrecy of the key....
-
Quantum communication complexity advantage implies violation of a Bell inequality
PublicationWe obtain a general connection between a quantum advantage in communication complexity and non-locality. We show that given any protocol offering a (sufficiently large) quantum advantage in communication complexity, there exists a way of obtaining measurement statistics which violate some Bell inequality. Our main tool is port-based teleportation. If the gap between quantum and classical communication complexity can grow arbitrarily...
-
Multiacces quantum communication and product higher rank numerical range
PublicationIn the present paper we initiate the study of the product higher rank numerical range. The latter, being a variant of the higher rank numerical range, is a natural tool for study- ing a construction of quantum error correction codes for multiple access channels. We review properties of this set and relate it to other numerical ranges, which were recently introduced in the literature. Further, the concept is applied to the construction...
-
Multi-criterion, evolutionary and quantum decision making in complex systems
PublicationMulti-criterion, evolutionary and quantum decision making supported by the Adaptive Quantum-based Multi-criterion Evolutionary Algorithm (AQMEA) has been considered for distributed complex systems. AQMEA had been developed to the task assignment problem, and then it has been applied to underwater vehicle planning as another benchmark three-criterion optimization problem. For evaluation of a vehicle trajectory three criteria have...
-
Directed percolation effects emerging from superadditivity of quantum networks
PublicationEntanglement-induced nonadditivity of classical communication capacity in networks consisting of quantum channels is considered. Communication lattices consisting of butterfly-type entanglement-breaking channels augmented, with some probability, by identity channels are analyzed. The capacity superadditivity in the network is manifested in directed correlated bond percolation which we consider in two flavors: simply directed and...
-
Hybrid quantum-classical approach for atomistic simulation of metallic systems
PublicationThe learn-on-the-fly (LOTF) method [G. Csanyi et al., Phys. Rev. Lett. 93, 175503 (2004)] serves to seamlessly embed quantum-mechanical computations within a molecular-dynamics framework by continual local retuning of the potential's parameters so that it reproduces the quantum-mechanical forces. In its current formulation, it is suitable for systems where the interaction is short-ranged, such as covalently bonded semiconductors....
-
The issues of quantum in empirical research on machines and other power systems
PublicationW pracy uzasadniono, że w badaniach naukowych systemów empirycznych, zwłaszcza maszyn jak również i innych urządzeń energetycznych, należy uwzględnić istniejącą w ich eksploatacji przypadkowość i nieprzewidywalność zdarzeń. Nawiązano do osiągnięć mechaniki kwantowej wskazując na wynikający z nich postulat, że wielkości nazywane komplementarnymi, mają istotną własność, która polega na tym, że niemożliwy jest jednoczesny i zarazem...
-
Analytical studies of spectrum broadcast structures in quantum Brownian motion
PublicationSpectrum broadcast structures are a new and fresh concept in the quantum-to-classical transition, introduced recently in the context of decoherence and the appearance of objective features in quantum mechanics. These are specific quantum state structures, responsible for the objectivization of the decohered state of a system. Recently, they have been demonstrated by means of the well-known quantum Brownian motion model of the recoilless...
-
Statistical properties of a modified standard map in quantum and classical regimes
PublicationWe present a model—a modified standard map. This model has interesting properties that allow quantum–classical correspondences to be studied. For some range of parameters in the classical phase space of this model, there exist large accelerator modes. We can create a family of maps that have large accelerator modes.
-
Formation of carbon monoxide by radiative association: a quantum dynamical study
PublicationRate coefficients for the formation of carbon monoxide (CO) by radiative association of carbon and oxygen atoms are computed using quantum dynamical simulations. At temperatures above 10 K CO radiative association is dominated by C(3P) and O(3P) approaching on the A1Π potential energy curve. The rate coefficient is estimated as k=A(T/300 K)αexp−β/T with A= 1.39 × 10−18 cm3 s−1, α=−0.016 and β= 92.2 for temperatures between 6 and...
-
Sharp transitions in low-number quantum dots Bayesian magnetometry
PublicationWe consider Bayesian estimate of static magnetic field, characterized by a prior Gaussian probability distribution, in systems of a few electron quantum dot spins interacting with infinite temperature spin environment via hyperfine interaction. Sudden transitions among optimal states and measurements are observed. Usefulness of measuring occupation levels is shown for all times of the evolution, together with the role of entanglement...
-
On entaglement distillation and quantum error correction of unknown states and channels.
PublicationBadano niezmienniczości splątania kwantowego oraz pojemności kwantowego kanału ze względu na ewentualną utratę informacji o pojedynczej kopii kwantowego stanu. Pokazano, że jeżeli dany kwantowy kanał ma pewne pojemności niezerowe, to odpowiadające mu stany posiadają niezerowe destylowalne splątanie. Postawiono pewne otwarte problemy dotyczące destylowalności splątania.
-
A new look at two polymorphic crystal structures of dibenzoylmethane: relationship between the crystal packing and the hydrogen atom position revealed by quantum chemistry and quantum crystallography methods
Publication -
Ciąża, poród i powikłania po porodzie w traktacie „O chorobach kobiet” Metrodory z Bizancjum,
Publication -
Dbałość o urodę kobiet na podstawie traktatów Metrodory z Bizancjum i Trotuli z Salerno
Publication -
Characteristic equations for the lasing modes of infinite periodic chain of quantum wires
Publication -
Low-threshold lasing eigenmodes of an infinite periodic chain of quantum wires
Publication -
Unconditional privacy over channels which cannot convey quantum information
PublicationQuantum cryptography enables one to verify that the state of the quantum system has not been tampered with and thus one can obtain privacy regardless of the power of the eavesdropper. All previous protocols relied on the ability to faithfully send quantum states or equivalently to share pure entanglement. Here we show this need not be the case-one can obtain verifiable privacy even through some channels which cannot be used to...
-
Electronic correlations in coherent transport through a two quantum dot system
Publication -
Natural carbon-based quantum dots and their applications in drug delivery: A review
Publication -
Measurement and analysis of absolute quantum yield of Rhodamine B doped PMMA
Publication -
Mixed, quantum-classical description of electron density transfer in the collision process
PublicationIn this work, we investigate an ion-atom model describing the time-dependent evolution of electron density during the collision. For a S3+- H system, numerical simulations are based on classical trajectory calculations, and the electron density behaviour is described with the time-dependent Schrödinger equation. We apply the finite difference method to obtain quantitative insights into the charge transfer dynamics, providing detailed...
-
Multi-criterion decision making in distributed systems by quantum evolutionary algorithms
PublicationDecision making by the AQMEA (Adaptive Quantum-based Multi-criterion Evolutionary Algorithm) has been considered for distributed computer systems. AQMEA has been extended by a chromosome representation with the registry of the smallest units of quantum information. Evolutionary computing with Q-bit chromosomes has been proofed to characterize by the enhanced population diversity than other representations, since individuals represent...
-
Tip-Based Nanofabrication as a Rapid Prototyping Tool for Quantum Science and Technology
PublicationTip-Based Nanofabication as a Rapid Prototyping Tool for Quantum Science and Technology discusses the development of cantilevered nanotips techniques of quantum devices prototyping and how they evolved from scanning probe microscopy. Also covered are the advantages and future prospects of atomic resolution capability and how to use this enabling technology as a rapid prototyping tool for quantum science and technology.
-
Objectivity in a Noisy Photonic Environment through Quantum State Information Broadcasting
PublicationRecently, the emergence of classical objectivity as a property of a quantum state has been explicitly derived for a small object embedded in a photonic environment in terms of a spectrum broadcast form—a specific classically correlated state, redundantly encoding information about the preferred states of the object in the environment. However, the environment was in a pure state and the fundamental problem was how generic and robust...
-
Quantum-correlation breaking channels, broadcasting scenarios, and finite Markov chains
PublicationOne of the classical results concerning quantum channels is the characterization of entanglementbreakingchannels [M. Horodecki et al., Rev. Math. Phys 15, 629 (2003)]. We address the questionwhether there exists a similar characterization on the level of quantum correlations which may gobeyond entanglement. The answer is fully affirmative in the case of breaking quantum correlationsdown to the, so called, QC (Quantum-Classical)...
-
Quantum corrections to 4 model solutions and applications to Heisenberg chain dynamics
PublicationThe Heisenberg spin chain is considered in φ^4 model approximation. Quantum corrections to classical solutions of the one-dimensional φ^4 model within the correspondent physics are valuated with account of rest d − 1 dimensions of a d-dimensional theory. A quantization of the model is considered in terms of space- time functional integral. The generalized zeta-function formalism is used to renormalize and evaluate the functional...
-
Pareto Task Assignments by an Adaptive Quantum-based Evolutionary Algorithm AQMEA
PublicationW pracy scharakteryzowano state_of_the_art w zakresie kwantowych algorytmów ewolucyjnych. Scharakteryzowano zasady efektywnego projektowania tej klasy algorytmów genetycznych. Podano wyniki uzyskane za pomocą kwantowego algorytmu ewolucyjnego AQMEA w zakresie wyznaczanie przydziałów zadań optymalnych w sensie Pareto.
-
The photocurrent quantum efficiency dependence on the applied voltage in organic solar cells
PublicationWe demonstrate that our recently reported model (Szmytkowski 2007 J. Phys. D: Appl. Phys. 40 3352) of the photocurrent quantum efficiency in organic semiconductors explains the external quantum efficiency dependence on the electric field in organic solar cells. This effect can be explained by taking into account that the photogeneration of charge carriers occurs via the electron-hole pair dissociation and the space charge effects...
-
Solution of coupled integral equations for quantum scattering in the presence of complex potentials
PublicationIn this paper, we present a method to compute solutions of coupled integral equations for quantum scattering problems in the presence of a complex potential. We show how the elastic and absorption cross sections can be obtained from the numerical solution of these equations in the asymptotic region at large radial distances.