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Semiconductor Physics Quantum Electronics & Optoelectronics
Journals 
Quantum Coherence as a Resource
PublicationThe coherent superposition of states, in combination with the quantization of observables, represents one of the most fundamental features that mark the departure of quantum mechanics from the classical realm. Quantum coherence in manybody systems embodies the essence of entanglement and is an essential ingredient for a plethora of physical phenomena in quantum optics, quantum information, solid state physics, and nanoscale thermodynamics....

Relativity of arithmetic as a fundamental symmetry of physics
PublicationArithmetic operations can be defined in various ways, even if one assumes commutativity and associativity of addition and multiplication, and distributivity of multiplication with respect to addition. In consequence, whenever one encounters ‘plus’ or ‘times’ one has certain freedom of interpreting this operation. This leads to some freedom in definitions of derivatives, integrals and, thus, practically all equations occurring in...

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 onedimensional φ^4 model within the correspondent physics are valuated with account of rest d − 1 dimensions of a ddimensional theory. A quantization of the model is considered in terms of space time functional integral. The generalized zetafunction formalism is used to renormalize and evaluate the functional...

Quantum corrections to phi^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 onedimensional φ^4 model within the correspondent physics are evaluated with account of rest d−1 dimensions of a ddimensional theory. A quantization of the model is considered in terms of spacetime functional integral. The generalized zetafunction formalism is used to renormalize and evaluate the functional integral...

Jan Kozicki dr hab. inż. arch.
PeopleIn year 2002 after obtaining master's degree in construction was employed on Faculty of Civil and Environmental Engineering. In 2004 obtained master's degree in architecture on Faculty of Architecture focusing on a research outpost on Mars. Defended PhD in year 2007 in the field of numerical modeling. In 2013 obtained Licentiate degree in theoretical physics on University of Gdańsk. In year 2014 obtained habilitation in technical...

Local hidden–variable models for entangled quantum states
PublicationWhile entanglement and violation of Bell inequalities were initially thought to be equivalent quantum phenomena, we now have different examples of entangled states whose correlations can be described by local hiddenvariable models and, therefore, do not violate any of the Bell inequalities. We provide an uptodate overview of the existing literature regarding local hiddenvariable models for entangled quantum states, in both...

Evaluating experimental molecular physics studies of radiation damage in DNA*
PublicationThe field of Atomic and Molecular Physics (AMP) is a mature field exploring the spectroscopy, excitation, ionisation of atoms and molecules in all three phases. Understanding of the spectroscopy and collisional dynamics of AMP has been fundamental to the development and application of quantum mechanics and is applied across a broad range of disparate disciplines including atmospheric sciences, astrochemistry, combustion and environmental...

Monitoring of the Process of System Information Broadcasting in Time
PublicationOne of the problems of quantum physics is how a measurement turns quantum, noncopyable data, towards copyable classical knowledge. We use the quantum state discrimination in a central system model to show how its evolution leads to the broadcasting of the information, and how orthogonalization and decoherence factors allow us to monitor the distance of the state in question to the one perfectly broadcasting information, in any...

Crystallization of space: Spacetime fractals from fractal arithmetic
PublicationFractals such as the Cantor set can be equipped with intrinsic arithmetic operations (addition, subtraction, multiplication, division) that map the fractal into itself. The arithmetics allows one to define calculus and algebra intrinsic to the fractal in question, and one can formulate classical and quantum physics within the fractal set. In particular, fractals in spacetime can be generated by means of homogeneous spaces associated...

Entanglement and Nonlocality are Inequivalent for Any Number of Parties
PublicationUnderstanding the relation between nonlocality and entanglement is one of the fundamental problems in quantum physics. In the bipartite case, it is known that these two phenomena are inequivalent, as there exist entangled states of two parties that do not violate any Bell inequality. However, except for a single example of an entangled threequbit state that has a local model, almost nothing is known about such a relation in multipartite...

Quantum corections to SG equation solutions and applications
Publication 
Quantum entanglement
PublicationAll our former experience with application of quantum theory seems to say that what is predicted by quantum formalism must occur in the laboratory. But the essence of quantum formalismentanglement, recognized by Einstein, Podolsky, Rosen, and Schrödingerwaited over 70 years to enter laboratories as a new resource as real as energy. This holistic property of compound quantum systems, which involves nonclassical correlations between...

Cartoon computation: Quantumlike algorithms without quantum mechanics
PublicationZaproponowano formalizm prowadzący do algorytmów analogicznych do kwantowych, lecz wykorzystujący jedynie struktury geometryczne. Jako przykład sformułowano odpowiednik kwantowego algorytmu DeutschaJozsy.

Correlation experiments in nonlinear quantum mechanics
PublicationPokazano w jaki sposób należy obliczać wieloczasowe i wielocząstkowe funkcje korelacyjne w nieliniowej mechanice kwantowej, aby zagwarantować lokalność formalizmu.

Bipartite correlations in quantum resonance states
Publication 
Aspects of multistation quantum information broadcasting
PublicationWe study quantum information transmission over multiparty quantum channel. In particular, we show an equivalence of different capacity notions and provide a multiletter characterization of a capacity region for a general quantum channel with k senders and m receivers. We point out natural generalizations to the case of twoway classical communication capacity. (C) 2010 Elsevier B.V. All rights reserved.

A macroscopic device for quantum computation
PublicationPrzeanalizowano mechaniczny model kwantowego układu 2bitowego. Model jest zilustrowany algorytmem Deutscha i Arvinda.

A simple test for quantum channel capacity
PublicationBased on state and channel isomorphism we point out that semidefiniteprogramming can be used as a quick test for nonzero oneway quantum channelcapacity. This can be achieved by searching for symmetric extensions of statesisomorphic to a given quantum channel. With this method we provide examplesof quantum channels that can lead to high entanglement transmission but stillhave zero oneway capacity, in particular, regions of symmetric...

Dressing method in matter + radiation quantum models
PublicationRozważane są modele typu Dicka i JaynesCummings'a, i obliczono widmo zaburzonego modelu Dicka. Wyprowadzono równania łańcuchowe ubierania.

Twoelectron entanglement in elliptically deformed quantum dots
Publication 
Investigation of rotational statechanging collisions of CCN$^{}$ ions with helium
PublicationMolecular anions which contain carbon chains, like C$_{4}$N$^{}$ and C$_{6}$N$^{}$, have already been found in the interstellar medium [1]. There is still no evidence for the existence of C$_{2}$N$^{}$ in interstellar medium. However, it is well known, that the molecule C$_{2}$N can form stable anions [2]. Because of their large dipole moments, these species have large rotational cross sections for rotational inelastic collisions...

Measuring quantum entanglement without prior state reconstruction.
PublicationWykazano, że w przypadku dwóch kubitów splątanie formowania może być mierzone bez rekonstrukcji stanu kwantowego.

Leszek Ziemczonek dr
PeopleUniversity education 19731978 – Nicolaus Copernicus University in Toruń, University of Gdańsk in Gdańsk, Mathematical Physics, M. Sc. 1979 – Diploma of Postgraduate Studies, Pedagogics 1989 – Institute of Physics, Polish Academy of Sciences in Warsaw, Theoretical Physics, Ph. D. 20102012 – Diploma of Postgraduate Studies, Mathematics Training: · 09.1983 – Trieste (Italy) – International Centre for Theoretical Physics...

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.

The optimized Rayleigh–Ritz scheme for determining the quantummechanical spectrum
Publication 
Analytical studies of spectrum broadcast structures in quantum Brownian motion
PublicationSpectrum broadcast structures are a new and fresh concept in the quantumtoclassical 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 wellknown quantum Brownian motion model of the recoilless...

Entanglement in S states of twoelectron quantum dots with Coulomb impurities at the center
Publication 
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.

Direct estimation of elements of algebra of quantum states and entanglement detection via linear contraction.
PublicationWykazano możliwość obliczenia elementów algebry generowanej przez macierze bez uprzedniej rekonstrukcji stanu. Ponadto wykazano, że pewne testy separowalności oparte o liniowe operacje zwężające można przeprowadzić bez uprzedniej rekonstrukcji badanych stanów.

Time travel without paradoxes: Ring resonator as a universal paradigm for looped quantum evolutions
PublicationA ring resonator involves a scattering process where a part of the output is fed again into the input. The same formal structure is encountered in the problem of time travel in a neighborhood of a closed timelike curve (CTC). We know how to describe quantum optics of ring resonators, and the resulting description agrees with experiment. We can apply the same formal strategy to any looped quantum evolution, in particular to the...

General solution of quantum mechanical equations of motion with timedependent Hamiltonians: A Lie algebraic approach
PublicationThe unitary operators U(t), describing the quantum time evolution of systems with a timedependent Hamiltonian, can be constructed in an explicit manner using the method of timedependent invariants. We clarify the role of Liealgebraic techniques in this context and elaborate the theory for SU(2) and SU(1,1). In these cases we give explicit formulae for obtaining general solutions from special ones. We show that the constructions...

Excimerbased redinfrared organic light emitting diodes with very high quantum efficiency
PublicationW pracy opisano konstrukcję wydajnej organicznej ekscymerowej diody EL emitującej światło czerwone i podczerwone z wykorzystaniem organicznego kompleksu platyny.

Convex set of quantum states with positive partial transpose analysed by hit and run algorithm
PublicationThe convex set of quantum states of a composite K×K system with positive partial transpose is analysed. A version of the hit and run algorithm is used to generate a sequence of random points covering this set uniformly and an estimation for the convergence speed of the algorithm is derived. For K >3 or K=3 this algorithm works faster than sampling over the entire set of states and verifying whether the partial transpose is positive....

Lowenergy positron scattering from gasphase tetrahydrofuran: A quantum treatment of the dynamics and a comparison with experiments
PublicationIn this paper we report new quantum calculations of the dynamics for lowenergy positrons interacting with gaseous molecules of tetrahydrofuran. The new quantum scattering cross sections are differential and integral cross sections at collision energies between 1.0 and 25.0 eV and include a careful treatment of the additional effects on the scattering process brought about by the permanent dipole moment of the target molecule....

Automatic Regularization by Quantization in Reducible Representations of CCR: PointForm Quantum Optics with Classical Sources
PublicationElectromagnetic fields are quantized in a manifestly covariant way by means ofa class of reducible "centerofmass Nrepresentations" of the algebra of canonical commutationrelations (CCR). The fourpotential Aa(x) transforms in these representations as aHermitian fourvector field in Minkowski fourposition space (without change of gauge), butin momentum space it splits into spin1 massless photons and two massless scalars. Whatwe...

Quantum corrections to quasiperiodic solution of SineGordon model and periodic solution of phi^4 model
PublicationAnalytical form of quantum corrections to quasiperiodic solution of SineGordon model and periodic solution of phi^4 model is obtained through zeta function regularisation with account of all rest variables of a ddimensional theory. Qualitative dependence of quantum corrections on parameters of the classical systems is also evaluated for a much broader class of potentials u(x) = b^2 f(bx) + C with b and C as arbitrary real constants

Swapping Space for Time: An Alternative to TimeDomain Interferometry
PublicationYoung's doubleslit experiment [1] requires two waves produced simultaneously at two different points in space. In quantum mechanics the waves correspond to a single quantum object, even as complex as a big molecule. An interference is present as long as one cannot tell for sure which slit is chosen by the object. The more we know about the path, the worse the interference. In the paper we show that quantum mechanics allows for...

Piotr Płotka dr hab. inż.
PeoplePiotr Płotka received the M.Sc. and D.Eng. degrees in electronic engineering from the Gdansk University of Technology, Poland, in 1976 and 1985. In 2008 he received D.Sc. (Dr.Hab.) degree, also in electronic engineering, from the Institute of Electron Technology at Warsaw, Poland. From 1977 he was with Academy of Technology and Agriculture at Bydgoszcz, Poland and from 1981 with the Gdansk University of Technology. In cooperation...

Increased Certification of Semidevice Independent Random Numbers using Many Inputs and More Postprocessing
PublicationQuantum communication with systems of dimension larger than two provides advantages in information processing tasks. Examples include higher rates of key distribution and random number generation. The main disadvantage of using such multidimensional quantum systems is the increased complexity of the experimental setup. Here, we analyze a notsoobvious problem: the relation between randomness certification and computational requirements...

Refined theoretical study of radiative association: Cross sections and rate constants for the formation of SiN
PublicationRadiative association of silicon mononitride (SiN) in its two lowest molecular electronic states is studied through quantum and classical dynamics. Special attention is paid to the behavior of the cross section at high collision energies. A modified expression for the semiclassical cross section is presented which excludes transitions to continuum states. This gives improved agreement with quantum mechanical perturbation theory...

Linear game noncontextuality and Bell inequalities—a graphtheoretic approach
PublicationWe study the classical and quantum values of a class of oneand twoparty unique games, that generalizes the wellknown XOR games to the case of nonbinary outcomes. In the bipartite case the generalized XOR(XORd) games we study are a subclass of the wellknown linear games. We introduce a 'constraint graph' associated to such a game, with the constraints defining the game represented by an edgecoloring of the graph. We use the...

Teleportation of geometric structures in 3D
PublicationThe simplest quantum teleportation algorithms can be represented in geometric terms in spaces of dimensions 3 (for real state vectors) and 4 (for complex state vectors). The geometric representation is based on geometricalgebra coding, a geometric alternative to the tensorproduct coding typical of quantum mechanics. We discuss all the elementary ingredients of the geometric version of the algorithm: geometric analogs of states...

TINKTEP: A fully selfconsistent, mutually polarizable QM/MM approach based on the AMOEBA force field
PublicationWe present a novel quantum mechanical/molecular mechanics (QM/MM) approach in which a quantum subsystem is coupled to a classical subsystem described by the AMOEBA polarizable force field. Our approach permits mutual polarization between the QM and MM subsystems, effected through multipolar electrostatics. Selfconsistency is achieved for both the QM and MM subsystems through a total energy minimization scheme. We provide an expression...

Experimental generation of complex noisy photonic entanglement
PublicationWe present an experimental scheme based on spontaneous parametric downconversion to produce multiplephoton pairs in maximally entangled polarization states using an arrangement of two typeI nonlinear crystals. By introducing correlated polarization noise in the paths of the generated photons we prepare mixedentangled states whose properties illustrate fundamental results obtained recently in quantum information theory, in particular those...

Rotational statechanging collisions of C2H− and C2N− anions with He under interstellar and cold ion trap conditions: A computational comparison
PublicationWe present an extensive range of quantum calculations for the statechanging rotational dynamics involving two simple molecular anions that are expected to play some role in the evolutionary analysis of chemical networks in the interstellar environments, C2H− (X1Σ+) and C2N− (X3Σ−), but for which inelastic rates are only known for C2H−. The same systems are also of direct interest in modeling selective photodetachment experiments...

Predicting the viscosity and electrical conductivity of ionic liquids on the basis of theoretically calculated ionic volumes
PublicationSelected physical properties of the ionic liquids might be quantitatively predicted based on the volumes of the ions these systems are composed of. It is demonstrated that the ionic volumes calculated using relatively simple theoretical quantum chemistry methods can be utilised to estimate the viscosities and electrical conductivities of various commonly used ionic liquids. The fitting formulas of the exponential form are offered...

Charge dependence of fragmentation process induced by ion collisions with furan molecule
PublicationThe goal of this work is to describe the system evolution after ionmolecule interaction. We combine different quantum chemistry and statistical mechanics approaches in order to give extended description of the process. Herein we report on a recent study of the fragmentation mechanism of neutral, singly and doublyionized furan molecule in the gas phase.

Constructive entanglement test from triangle inequality
PublicationWe derive a simple lower bound on the geometric measure of entanglement for mixed quantum states in the case of a general multipartite system. The main ingredient of the presented derivation is the triangle inequality applied to the root infidelity distance in the space of density matrices. The obtained bound leads to entanglement criteria with a straightforward interpretation. The proposed criteria provide an experimentally accessible,...

Relativistic twodimensional hydrogenlike atom in a weak magnetic field
PublicationA twodimensional (2D) hydrogenlike atom with a relativistic Dirac electron, placed in a weak, static, uniform magnetic field perpendicular to the atomic plane, is considered. Closed forms of the first and secondorder Zeeman corrections to energy levels are calculated analytically, within the framework of the Rayleigh–Schrödinger perturbation theory, for an arbitrary electronic bound state. The secondorder calculations are...