This article reviews chosen topics related to the development of Information Quantum Technologies in the major areas of measurements, communications, and computing. These fields start to build their ecosystems which in the future will probably coalesce into a homogeneous quantum information layer consisting of such interconnected components as quantum internet, full size quantum computers with efficient error corrections and ultrasensitive quantum metrology nodes stationary and mobile. Today, however, the skepticism expressing many doubts about the realizability of this optimistic view fights with a cheap optimism pouring out of some popular press releases. Where is the truth? Financing of the IQT by key players in research, development and markets substantially strengthens the optimistic side. Keeping the bright side with some reservations, we concentrate on showing the FAST pace of IQT developments in such areas as biological sciences, quantum evolutionary computations, quantum internet and some of its components.

User authentication is an essential element of any communication system. The paper investigates the vulnerability of the recently published first semiquantum identity authentication protocol (Quantum Information Processing 18: 197, 2019) to the introduced herein multisession attacks. The impersonation of the legitimate parties by a proper combination of phishing techniques is demonstrated. The improved version that closes the identified loophole is also introduced

“Soon we will be able to fit the contents of the Encyclopedia Britannica on a head of a pin,” the famous physicist Richard Feynman argued back in the 1960s. Perhaps even he would be amazed at the possibilities now offered by carbon nanotubes, several hundred thousand times tinier than a pin. Their amazing properties have been exploited in an integrated circuit developed at the Karlsruhe Institut für Technologie.

Properties of excitons confined to potential fluctuations due to indium distribution in the wetting layer which accompany self-assembled InAs/GaAs quantum dots are reviewed. Spectroscopic studies are summarized including time-resolved photoluminescence and corresponding single-photon emission correlation measurements. The identification of charge states of excitons is presented which is based on results of a theoretical analysis of interactions between the involved carriers. The effect of the dots’ environment on their optical spectra is also shown.

We present a novel quantum algorithm for the classification of images. The algorithm is constructed using principal component analysis and von Neuman quantum measurements. In order to apply the algorithm we present a new quantum representation of grayscale images.

This research paper discusses an analytical approach to designing the active region of light emitting diodes to enhance its performance. The layers in the active region were modified and the effects of changing the width of quantum well and barrier layers in a multi-quantum light emitting diode on the output power and efficiency have been investigated. Also, the ratio of the quantum well width to the B layer width was calculated and proposed in this research paper. The study is carried out on two different LED structures. In the first case, the width of the quantum well layers is kept constant while the width of the B layers is varied. In the second case, both the quantum well and B layer widths are varied. Based on the simulation results, it has been observed that the LED power efficiency increases considerably for a given quantum well to B layers width ratio without increasing the production complexity. It is also seen that for a desired power efficiency the width of quantum well should be between 0.003 µm and 0.006 µm, and the range of B width (height) should be 2.2 to 6 times the quantum well width. The proposed study is carried out on the GaN-AlGaN-based multi-quantum well LED structure, but this study can be extended to multiple combinations of the semiconductor structures.

QIT–Quantum Information Technologies promises are very serious, greatly exceeding only technical and market levels. Development of QIT in Europe, treated as building a new infrastructural civilization level, requires a broader view of coordination, funding and priority-setting policy. Simple measures used in the case of the development of new technologies, but not creating a significant ecosystem, are insufficient in this case. Quantum technologies are poised to create a new information layer of knowledge-based society. In this essay, the author subjectively addresses some of the issues such as: what we already know and what we don't know, and what efforts are being made in Europe. Polish version of this paper was published in Przegl.Telekom.2.23.

In this work genetic programming is applied to the problem of generating maximum entanglement in multi-qubit systems of different structures. We provide quantum circuits that prepares multipartite entangled states in systems consisting of up to 8 qubits. We present results pertaining to the minimum size of a quantum circuit preparing a maximally entangled multi-qubit state in cases of reduced sets of quantum gates that correspond to spin chain quantum systems.

Length, width, depth… Knowing these parameters allows us to judge which table will fit into our dining room, which bed is right for our bedroom. We use three measures to describe the space around us, but we rarely ask ourselves whether reality is, in fact, three-dimensional.

The authors report the characteristics of a diffraction-grating-free mid-wavelength infrared InP/In0.85Ga0.15As quantum well infrared photodetector focal plane array with a 640 × 512 format and a 15 m pitch. Combination of a normal incident radiation sensing ability of the high-x InxGa1-xAs quantum wells with a large gain property of the InP barriers led to a diffraction-grating-free quantum well infrared photodetector focal plane array with characteristics displaying great promise to keep the status of the quantum well infrared photodetector as a robust member of the new generation thermal imaging sensor family. The focal plane array exhibited excellent uniformity with noise equivalent temperature difference nonuniformity as low as 10% and a mean noise equivalent temperature difference below 20 mK with f/2 optics at 78 K in the absence of grating. Elimination of the diffraction-grating and large enough conversion efficiency (as high as 70% at a −3.5 V bias voltage) abolish the bottlenecks of the quantum well infrared photodetector technology for the new generation very small-pitch focal plane arrays.

Europe has to face strong competitive challenges in the field of QIT from other regions of the world. The tools for the effective implementation of the challenges related to the start, we hope, of building a quantum civilization are both common and individual in particular European countries. Joint projects in the field of QIT, usually narrowly focused, are announced by large European Agencies and are related to their activities. Large-scale collaborative projects are of course the domain of the EC. National projects depend heavily on the capabilities of individual countries and vary greatly in size. The most technologically advanced European countries invest hundreds of millions of Euros in national QIT projects annually. The largest European FET class project currently being implemented is the Quantum Flagship. Although the EQF is basically just one of the elements of a large and complicated European scene of development of quantum technologies, it becomes the most important element and, in a sense, a dominant one, also supported from the political level. There are complex connections and feedbacks between the elements of this quantum scene. National projects try to link to the EQF. Here we are interested in such connections and their impact on the effectiveness of QIT development in Europe, and especially in Poland.

The aim of the paper is to show how graduated engineering students in classical ICT view practically the advent of the QIT. The students do their theses in El.Eng. and ICT and were asked how to implement now or in the future the QIT in their current or future work. Most of them have strictly defined research topics and in some cases the realization stage is advanced. Thus, most of the potential QIT application areas are defined and quite narrow. In such a case, the issue to be considered is the incorporation of QIT components and interfaces into the existing ICT infrastructure, software and hardware alike, and propose a solution as a reasonable functional hybrid system. The QIT components or circuits are not standalone in most cases, they should be somehow incorporated into existing environment, with a measurable added value. Not an easy task indeed. We have to excuse the students if the proposed solutions are not ripe enough. The exercise was proposed as an on-purpose publication workshop, related strictly to the fast and fascinating development of the QIT. The paper is a continuation of publishing exercises with previous groups of students participating in QIT lectures.

This paper is written by a group of Ph.D. students pursuing their work in different areas of ICT, outside the direct area of Information Quantum Technologies IQT. An ambitious task was undertaken to research, by each co-author, a potential practical influence of the current IQT development on their current work. The research of co-authors span the following areas of ICT: CMOS for IQT, QEC, quantum time series forecasting, IQT in biomedicine. The intention of the authors is to show how quickly the quantum techniques can penetrate in the nearest future other, i.e. their own, areas of ICT.

In this work we provide a method for approximating the separable numerical range of a matrix. We also recall the connection between restricted numerical range and entanglement of a quantum state. We show the possibility to establish state separability using computed restricted numerical range. In particular we present a method to obtain separability criteria for arbitrary system partition with use of the separable numerical range.

The compositional graded quaternary barriers (GQBs) instead of ternary/conventional quantum barriers (QBs) have been used to numerically enhance the efficiency of AlGaN-based ultraviolet light-emitting diode (LED). The performance of LED with GQBs is examined through carrier concentrations, energy band diagrams, radiative recombination, electron and hole flux, internal quantum efficiency (IQE), and emission spectrum. As a function of the operating current density, a considerable reduction in efficiency droop is observed in the device with composition-graded quaternary barriers as compared to the conventional structure. The efficiency droop in case of a conventional LED is ~77% which decreased to ~33% in case of the proposed structure. Moreover, the concentration of electrons and holes across the active region in case of the proposed structure is increased to ~156% and ~44%, respectively.

Quantum cascade laser is one of the most sophisticated semiconductor devices. Its technology requires extremely high precision and layers quality. Device performance is limited by thermal extraction form laser core. One of solutions is to apply highly resistivity epitaxial material acting as insulating layer on top of the QCL. Present work describes consequent steps of elaboration of MOVPE technology of Fe-compensated InP layers for further applications in quantum cascade lasers.

In this article we present a procedure that allows to synthesize optimal circuit representing any reversible function within reasonable size limits. The procedure allows to choose either the NCT or the MCT gate set and specify any number of ancillary qubits to be used in the circuit. We will explore efficacy of this procedure by synthesizing various sources of nonlinearity used in contemporary symmetric ciphers and draw conclusions about properties of those transformations in quantum setting. In particular we will try to synthesize optimal circuit representing ASCON cipher SBOX which recently won NIST competition for Lightweight Cryptography standard.

This paper investigates whether a quantum computer can efficiently simulate the non-elastic scattering of the Schrödinger particle on a stationary excitable shield. The return of the shield to the ground state is caused by photon emission. An algorithm is presented for simulating the time evolution of such a process, implemented on standard two-input gates. The algorithm is used for the computation of elastic and non-elastic scattering probabilities. The results obtained by our algorithm are compared with those obtained using the standard Cayley’s method.

Quantum logic emerged in the 1930s as a response to the question of whether the conceptual changes initiated in physics by quantum mechanics required a revision of logic. In the English-language literature, John von Neumann is considered the founder of quantum logic, while the Polish literature points to Zygmunt Zawirski. Zawirski was the first researcher who suggested that quantum mechanics may follow a different logic than classical logic. He was the first researcher in the field of manyvalued quantum logic, but his influence ultimately proved to be limited. John von Neumann, on the other hand, along with Garrett Birkhoff, started the now dominant field of algebraic quantum logic. It turns out that despite their differences in assumptions and methods, what they have in common is their commitment to subjecting the design of quantum logic to two requirements - consideration of Heisenberg's indeterminacy principle and reconciliation of the resulting logic with probability calculus.

High-power terahertz sources operating at room-temperature are promising for many applications such as explosive materials detection, non-invasive medical imaging, and high speed telecommunication. Here we report the results of a simulation study, which shows the significantly improved performance of room-temperature terahertz quantum cascade lasers (THz QCLs) based on a ZnMgO/ZnO material system employing a 2-well design scheme with variable barrier heights and a delta-doped injector well. We found that by varying and optimizing constituent layer widths and doping level of the injector well, high power performance of THz QCLs can be achieved at room temperature: optical gain and radiation frequency is varied from 108 cm⁻¹ @ 2.18 THz to 300 cm⁻¹ @ 4.96 THz. These results show that among II–VI compounds the ZnMgO/ZnO material system is optimally suited for high-performance room-temperature THz QCLs.

The article is a sort of advanced publication workshop prepared by a group of M.Sc. students in ICT participating in the course on QIT. The idea behind the publishing exercise is to try to link, if possible, individual own work just under realization for the thesis with new unique possibilities offered by the QIT. Each chapter is written by a single author defining concisely her/his research interest in the classical ICT field and trying to find possible correlations with respective abruptly developing branches of the QIT. The chapter texts are somehow moderated by the tutor but are exclusively authored by young researchers. The aim was to present their views on the possible development directions of particular subfields of QIT, if not fully mature, but still based on their own ideas, research and dreams.

This article discusses four fields of study with the potential to revolutionize our understanding and interaction with biological systems: quantum biophotonics, molecular and supramolecular bioelectronics, quantum-based approaches in gaming, and nano-biophotonics. Quantum biophotonics uses photonics, biochemistry, biophysics, and quantum information technologies to study biological systems at the sub-nanoscale level. Molecular and supramolecular bioelectronics aim to develop biosensors for medical diagnosis, environmental monitoring, and food safety by designing materials and devices that interface with biological systems at the molecular level. Quantum-based approaches in gaming improve modeling of complex systems, while nanomedicine enhances disease diagnosis, treatment, and prevention using nanoscale devices and sensors developed with quantum biophotonics. Lastly, nano-biophotonics studies cellular structures and functions with unprecedented resolution.

Post-Quantum Cryptography (PQC) attempts to find cryptographic protocols resistant to attacks by means of for instance Shor's polynomial time algorithm for numerical field problems like integer factorization (IFP) or the discrete logarithm (DLP). Other aspects are the backdoors discovered in deterministic random generators or recent advances in solving some instances of DLP. The use of alternative algebraic structures like non-commutative or non-associative partial groupoids, magmas, monoids, semigroups, quasigroups or groups, are valid choices for these new kinds of protocols. In this paper, we focus in an asymmetric cipher based on a generalized ElGamal non-arbitrated protocol using a non-commutative general linear group. The developed protocol forces a hard subgroup membership search problem into a non-commutative structure. The protocol involves at first a generalized Diffie-Hellman key interchange and further on the private and public parameters are recursively updated each time a new cipher session is launched. Security is based on a hard variation of the Generalized Symmetric Decomposition Problem (GSDP). Working with GF(2518) a 64-bits security is achieved, and if GF(25116) is chosen, the security rises to 127-bits. An appealing feature is that there is no need for big number libraries as all arithmetic if performed in Z251 and therefore the new protocol is particularly useful for computational platforms with very limited capabilities like smartphones or smartcards.