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1

Szkolenie atomów

Chwedeńczuk Jan

Postępy Fizyki

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2023

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T. 74, z. 3

2--4

PL

Atomy, jak rekruci, by się sprawdzić na kwantowym polu bitwy, muszą przejść przysposobienie. Skoszarowane w pułapkach magnetycznych nabierają ogłady, zaś poddane mozolnemu szkoleniu, stają się najbardziej elitarną grupą w znanym Wszechświecie - nielokalnie splątanym oddziałem do zadań specjalnych.

EN

Atoms, like recruits, to prove themselves on the quantum battlefield, must get some drill. Enclosed in magnetic traps they get familiar with each other, while, subjected to strenuous training, they become the most elite group in the known Universe - a non-locally entangled squad for special tasks.

2

Kwantowe splątanie ⋆ nierówności Bella ⋆ teoretyczne podstawy obserwacji interferencji wielofotonowej ⋆ narodziny technologii kwantowych

Żukowski Marek

Postępy Fizyki

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2023

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T. 74, z. 2

3--12

PL

W artykule przedstawiam za co i dlaczego John F. Clauser, Alain Aspect i Anton Zeilinger otrzymali Nagrodę Nobla 2022 (równo 100 lat po wręczeniu tejże nagrody Einsteinowi i Bohrowi), a także koncentruję się nad istotą prowadzonych przeze mnie badań, które wiążą się ze wspomnianą nagrodą. Tekst jest napisany dwutorowo. Czytelnik, szacując swój poziom wiedzy z fizyki kwantowej, może go czytać przeskakując pomiędzy tekstem głównym, a fragmentami z kropką (●) głębiej wyjaśniającymi pewne aspekty, ale można też przeczytać tylko tekst główny. Jako autor wolałbym, aby artykuł zainteresował nauczycieli i studentów, a może nawet licealistów, niż profesorów doktorów habilitowanych, choć i ci nie omijając fragmentów z kropką, mam nadzieję, mogą się czegoś ciekawego dowiedzieć.

EN

In the paper I describe why and for what achievements John F. Clauser, Alain Aspect and Anton Zeilinger received the Nobel Prize in 2022 (exactly 100 years after the prize had been awarded to Einstein and Bohr), as well as my own research related to the prize. The text is written in a twofold way. Based on familiarity with quantum physics the reader can switch between the main narrative and the parts marked with bullets (•) explaining some aspects in more detail, but one can restrict attention to the main text only. As the author, I would prefer that the paper be of interest to teachers, students, and possibly also high-school students rather than professors, although even they can learn something interesting, also from the parts marked with a bullet.

3

Internet kwantowy

Romaniuk Ryszard

Elektronika : konstrukcje, technologie, zastosowania

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2022

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Vol. 63, Nr 5

19--25

PL

Fundamentalne twierdzenia o niemożliwościach kwantowych są związane łącznie z zasadami zachowania energii w systemie zamkniętym, zakazem Pauliego i twierdzeniem spin-statystyka, zasadą nieoznaczoności Heisenberga, wykluczeniem prędkości superluminalnej, paradoksem informacyjnym czarnej dziury, jej parowaniem i trójparametrowym opisem w postaci tylko masy, ładunku elektrycznego i momentu obrotowego, determinizmem kwantowym i odwracalnością czasu (symetrią CPT), ciągłym wielokanałowym sprzężeniem mikro świata kwantowego z makroświatem termodynamicznym objawiającym się dynamiką wyboru dekoherencji, itp. W tak zdefiniowanym przy pomocy twardych ograniczeń obszarze zadaniem do realizacji jest budowa kwantowego złożonego, technicznego systemu funkcjonalnego. Dostępnym budulcem są kubity, kudity, bramki i układy oraz pamięci kwantowe, itp. Ogólnym zasobem sygnałowym w kwantowych technikach informacyjnych ITK jest nielokalność, możliwość jej opanowania technicznego, oraz jej potencjalna ocena ilościowa i jakościowa, często odnoszona do poziomu LOCC. W szczególności, nie do końca ekwiwalentnymi, zasobami są diskord kwantowy, kontekstualność, kwantowa entropia, a najczęściej splątanie. Narzędziami do budowy systemów ITK są teleportacja kwantowa, tomografia kwantowa, współdzielenie stanów splątanych, sterowanie kubitów fizycznych i logicznych, wirtualizacja kubitów, destylacja splątania, korekcja błędów kwantowych, transfer stanów kwantowych między kubitami stacjonarnymi i lotnymi, itp. Celem jest budowa Internetu kwantowego, docelowo całkowicie kwantowego, a obecnie w wersji NISQ.

EN

Fundamental quantum no-go theorems are related to the principles of conservation of energy in a closed system, the Pauli exclusion principle and the spin-statistics theorem, the Heisenberg uncertainty principle, the exclusion of superluminal velocity, the black hole information paradox, its evaporation and the only three-parameter description with mass, electric charge and angular momentum, quantum determinism and time reversibility (CPT symmetry), continuous multichannel coupling of the quantum micro world with the thermodynamic macro world manifested by the dynamics of decoherence selection rules, etc. The available building blocks are qubits, kudits, gates and circuits, quantum memories, etc. The general signal resource in IQT is nonlocality, the possibility of its harnessing at the technical level, and its potential quantitative and qualitative assessment, often related to the LOCC level. In particular, not entirely equivalent resources are quantum discord, contextuality, quantum entropy, and most often the entanglement. The tools for building IQT are quantum teleportation, quantum tomography, entangled states sharing, control of physical and logical qubits, qubit virtualization, entanglement distillation, correction of quantum errors, transfer of quantum states between stationary and flying qubits, etc. The goal is to build a quantum Internet, ultimately entirely quantum, and currently in the NISQ version.

4

Satellite Orbit Determination using Quantum Correlation Technology

Zhang B., Sun F., Zhu X., Jia X.

Acta Geophysica

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2018

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Vol. 66, no. 2

233--241

EN

After the presentation of second-order correlation ranging principles with quantum entanglement, the concept of quantum measurement is introduced to dynamic satellite precise orbit determination. Based on the application of traditional orbit determination models for correcting the systematic errors within the satellite, corresponding models for quantum orbit determination (QOD) are established. This paper experiments on QOD with the BeiDou Navigation Satellite System (BDS) by first simulating quantum observations of 1 day arc-length. Then the satellite orbits are resolved and compared with the reference precise ephemerides. Subsequently, some related factors influencing the accuracy of QOD are discussed. Furthermore, the accuracy for GEO, IGSO and MEO satellites increase about 20, 30 and 10 times, respectively, compared with the results from the resolution by measured data. Therefore, it can be expected that quantum technology may also bring delightful surprises to satellite orbit determination as have already emerged in other fields.

5

Higher-order quantum dynamics of a generic quadratically-coupled optomechanical system: entanglement, antibunching and spin squeezing

Mukherjee K., Jana P. C.

Optica Applicata

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2017

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Vol. 47, nr 4

651--663

EN

To investigate the existence of higher-order intermodal entanglement, higher-order single-mode antibunching, higher-order intermodal antibunching and spin squeezing, a first order analytic operator solution of the Hamiltonian of quadratically-coupled optomechanical system is constructed using short time approximation for different field modes. Temporal variations of these nonclassical properties under different coupling strengths are studied, neglecting the effect of optical losses, environmental effects and also dissipation. With an increasing order number, the depth of these nonclassical properties is increased. Spin squeezed states are observed in any direction, i.e., either in Sx or Sy direction.

6

Research on the Mechanical Properties and Curing Networks of Energetic GAP/TDI Binders

Ma S., Li Y., Li Y., Li G., Luo Y.

Central European Journal of Energetic Materials

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2017

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Vol. 14, no. 3

708--725

EN

This research focused on correlations between the macroscopic mechanical performance and microstructures of energetic binders. Initially a series of glycidyl azide polymer (GAP)/toluene diisocyanate (TDI) binders, catalyzed by a mixture of dibutyltin dilaurate (DBTDL) and triphenyl bismuth (TPB), was prepared. Uniaxial tensile testing, and low-field nuclear magnetic resonance and infrared spectroscopy were then used to investigate the mechanical properties, curing networks, and hydrogen bonding (H-bonds) of these binders. Additionally, a novel method based on the molecular theory of elasticity and the statistical theory of rubber elasticity was used to analyze the integrity of the networks. The results showed that the curing parameter R strongly influences the mechanical properties and toughness of the binders, and that a tensile stress (σm) of 1.6 MPa and an elongation (εm) of 1041% was observed with an R value of 1.6. The cross-linking density increased sharply with the curing parameter, but only modestly with an R value ≥ 1.8. The proportion of H-bonds formed by the imino groups increased with the R value and reached 72.61% at an R value of 1.6, indicating a positive correlation between the H-bonds and σm. Molecular entanglement was demonstrated to increase with R and to contribute dramatically to the mechanical performance. The integrity of these networks, evaluated by a correction factor (A), varies with R, and a network of the GAP/TDI binder with an R value of 1.6 is desirable.

7

Entangled State Creation by a Nonlinear Coupler Pumped in Two Modes

Duc V. E., Long V. C.

Computational Methods in Science and Technology

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2016

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Vol. 22, No. 4

245--252

EN

In this paper we consider a system with two nonlinear oscillators which are coupled via a nonlinear interaction. In order to excite the system, we use two external coherent fields. Two oscillators have different frequencies. It follows from numerical simulation that evolution of the system is similar to that of a combination of n-photon states. Therefore, the considered system behaves as so-called nonlinear quantum scissor. Nevertheless, evolution of the system generates Bell-like states in several times with very high probability. Because of the nonlinear properties of oscillators and their interaction, the system creates a truncation of optical states, which leads to obtain two-qubit states. It will also be shown that these states appear several times in the qutrit-qutrit system.

8

Faces for two-qubit separable states and the convex hulls of trigonometric moment curves

Kye S.-H.

Probability and Mathematical Statistics

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2013

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Vol. 33, Fasc. 2

385--400

EN

We analyze the facial structures of the convex set consisting of all two-qubit separable states. One of the faces is a four-dimensional convex body generated by the trigonometric moment curve arising from polyhedral combinatorics. Another one is an eight-dimensional convex body, which is the convex hull of a homeomorphic image of the two-dimensional sphere. Extreme points consist of points on the surface, and any two of tchem determine an edge. We also reconstruct the trigonometric moment curve in any even-dimensional affine space using the qubit-qudit systems, and characterize the facial structures of the convex hull.

9

Modes, modals, and barycentric algebras: a brief survey and an additivity theorem

Smith J. D. H.

Demonstratio Mathematica

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2011

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Vol. 44, nr 3

571-587

EN

Modes are idempotent and entropic algebras.Modals are both join semi lattices and modes,where the mode structure distributes over the join.Barycentric algebras are equipped with binary operations from the open unit interval,satisfying idempo tence,skew commutativity,and skew associativity.The article aims to give a brief survey of these structures and some of their applications.Special attention is devoted to hierar chical statistical mechanics and the modeling of complex systems.An additivity theorem for the entropy of independent combinations of systems is proved.

10

Możliwości przesyłania informacji w sieciach z wykorzystaniem efektów kwantowych

Miszczak J. A.

Studia Informatica

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2003

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Vol. 24, nr 2A

87-95

PL

Mechanika kwantowa umożliwia przesyłanie informacji w sposób niemożliwy w modelu klasycznym. Przykładami wykorzystania efektów kwantowych jest teleportacja kwantowa oraz gęste kodowanie. Kwantowy charakter kanałów informacyjnych może także zapewnić bezpieczny przesył poufnych informacji.

EN

Quantum mechanics allows faster and more efficent communication that it is possible in the clasical model. Two most important examples of quantum, effects, which can be used in computer networks, are : quantum teleportation and dense coding. Quantum channels can also be applied to secure comunication