The goal of this International Roadmap for Devices and Systems (IRDS) chapter is to survey, catalog, and assess the status of technologies in the areas of cryogenic electronics and quantum information processing. Application drivers are identified for sufficiently developed technologies and application needs are mapped as a function of time against projected capabilities to identify challenges requiring research and development effort. Cryogenic electronics (also referred to as low-temperature electronics or cold electronics) is defined by operation at cryogenic temperatures (below −150 °C or 123.15 K) and includes devices and circuits made from a variety of materials including insulators, conductors, semiconductors, superconductors, or topological materials. Existing and emerging applications are driving development of novel cryogenic electronic technologies. Information processing refers to the input, transmission, storage, manipulation or processing, and output of data. Information processing systems to accomplish a specific function, in general, require several different interactive layers of technology. A top-down list of these layers begins with the required application or system function, leading to system architecture, micro- or nano-architecture, circuits, devices, and materials. A fundamental unit of information (e.g., a bit) is represented by a computational state variable, for example, the position of a bead in the ancient abacus calculator or the voltage (or charge) state of a node capacitance in CMOS logic. A binary computational state variable serves as the foundation for von Neumann computational system architectures that dominated conventional computing. Quantum information processing is different in that it uses qubits, two-state quantum-mechanical systems that can be in coherent superpositions of both states at the same time, which can have computational advantages. Measurement of a qubit in a given basis causes it to collapse to one of the basis states. Technology categories covered in this report include: • Superconductor electronics (SCE) • Cryogenic semiconductor electronics (Cryo-Semi) • Quantum information processing (QIP)
Continuing miniaturization of electronic devices, together with the quickly growing number of nanotechnological applications, demands a profound understanding of the underlying physics. Most of the fundamental problems of modern condensed matter physics involve various aspects of quantum transport and fluctuation phenomena at the nanoscale. In nanostructures, electrons are usually confined to a limited volume and interact with each other and lattice ions, simultaneously suffering multiple scattering events on impurities, barriers, surface imperfections, and other defects. Electron interaction with other degrees of freedom generally yields two major consequences, quantum dissipation and quantum decoherence. In other words, electrons can lose their energy and ability for quantum interference even at very low temperatures. These two different, but related, processes are at the heart of all quantum phenomena discussed in this book.This book presents copious details to facilitate the understanding of the basic physics behind a result and the learning to technically reproduce the result without delving into extra literature. The book subtly balances the description of theoretical methods and techniques and the display of the rich landscape of the physical phenomena that can be accessed by these methods. It is useful for a broad readership ranging from master's and PhD students to postdocs and senior researchers.
The materials of The International Scientific – Practical Conference is presented below.
The Conference reflects the modern state of innovation in education, science, industry and social-economic sphere, from the standpoint of introducing new information technologies.
It is interesting for a wide range of researchers, teachers, graduate students and professionals in the field of innovation and information technologies.
Exceptionally strong enhancement of the Raman signal exceeding eight orders of magnitude for near-infrared (1064 nm) excitation is demonstrated for an array of dielectric submicron pillars covered by a relatively thick metal layer. The microstructure is designed to support ‘spoof’ plasmon-polariton excitations with resonant frequencies significantly below the fundamental surface plasmon resonance. Experiments reveal a relatively narrow range of spatial parameters for the optimal resonant scattering enhancement. They include a period close to the excitation wavelength, a specific ratio of the pillar planar size to the period, and optimal heights of both the pillars and the covering silver metal layer. The realized microstructures can be produced by fab-compatible photolithography techniques, and their outstanding sensing possibilities open the venue for the biomedical applications.
We have studied the catalytic activity of Cu–Ni bimetallic catalysts on yttrium-, tin-, zinc-, and niobium-doped zirconia and ceria supports for methanol steam reforming (MSR), a process for hydrogen production, and examined the effect of the nature of the dopants and annealing temperature on the structure and particle size of the oxide supports and the catalytic activity of the metal oxide composites. In all cases, the addition of heterovalent ions improved the catalytic activity of the materials for the MSR process in comparison with undoped zirconia. The highest hydrogen yield was reached in the case of catalysts doped with niobium and yttrium oxides.
A new perfluorinated sulfocationic polymer and a membrane based thereon have been produced using the thermally initiated high-pressure polymerization. The proton conductivity of obtained material is higher than that of commercial Nafion membranes and reaches 57 mS cm–1 at 21 C and 114 mS cm–1 at 79 C.
Results of hydrogen production study in methanol steam reforming (MSR) process with the use of Ru0.5eRh0.5 catalysts supported on different carbon materials: synthetic graphitelike material Sibunit, carbon black Ketjenblack EC600DJ, detonation nanodiamonds (DND) and ZrO2-based material with fluorite structure, doped with ceria, have been described. The samples have been tested in conventional flow reactor and membrane (MR) reactor, containing Pd-based membranes with different composition, thickness and surface architecture. It has been shown that the catalytic activity of the composites depends on the support nature. The RueRh/DND catalyst exhibits the highest activity, whereas Rue Rh/Ce0.1Zr0.9O2ed is the most selective. The use of PdeAg (23%) foil with the surface modified by palladium black showed great advantages comparing to the smooth dense membrane. The use of the MR with the PdeAg membrane improves the MSR reaction and provides almost 50% increase in the hydrogen yield. The hydrogen produced with the use of the MR is ultra pure.
In the present paper, the influence of acid–base properties of inorganic particles in ion-exchange membrane-based nanocomposites on their physicochemical and transport properties was investigated. For this purpose, particles of Zr, Ti, and Si oxides have been synthesized in situ in the system of pores and channels of the membranes. Depending on the acid–base properties of oxides, introduction of nanoparticles can increase or decrease the water uptake, conductivity, and selectivity. A new approach to crosslinking of ion-exchange membranes by incorporating ZrO2 particles into their matrix is proposed. Such cross-linking provides an improvement of swelling, conductivity, and salt permselectivity of the membrane in Na+-form. These parameters are important for successful application of such materials in direct and reverse electrodialysis, electrodeionization, and diffusion dialysis. For example, incorporation of 10 wt% of zirconia leads to a Bcross-linking^ of the membrane, i.e., binding of 45–50% of sulfonic groups, accompanied by a decrease of the water uptake by more than twofold and an increase of apparent transport numbers.
We have synthesized hybrid membranes based on N-phosphorylated polybenzimidazole, containing different percentages of silica (2–20 wt %). The materials have been characterized by scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, IR spectroscopy, and impedance spectroscopy. The membranes have been shown to contain silica nanoparticles with a bimodal size distribution: 3–5 and 20–60 nm. The hybrid membranes have high proton conductivity (9.7 mS/cm at 130°C), which has a maximum when the dopant content is 2–10 wt %. The phosphonic groups grafted onto the polymer ensure additional hydration of the membranes at increased humidity. The addition of silica helps to reduce the gas permeability of the membranes by a factor of ~1.5
Opal matrix is a regular 3D-packing of spherical particles of amorphous SiO2, forming an ordered system of voids. Opal matrixes with spherical particles of SiO2 diameter d ≈ 260 nm (Δd ≈ 2 %) were synthesized. The frequency dependences of the conductivity, real and imaginary components of the dielectric and magnetic conductivity of nanocomposites containing crystallites 16–65 nm in size of magnetic materials ‒ double phosphates (LiNiPO4, LiCoPO4) and vanadates (GdVO4 and DyVO4) were measured. The dielectric losses of nanocomposites remain low (at a level of ~ 0.06) in the frequency range 107–1010 Hz for nanocomposites with DyVO4 and LiCoPO4. The dielectric loss increases both in the direction of low frequencies (< 106 Hz) and in the direction of THz frequencies.
The interactions among fluid species such as H2O, CO2, and CH4 confined in nano- and meso-pores in shales and other rocks is of central concern to understanding the chemical behavior and transport properties of these species in the earthâ€™s subsurface and is of special concern to geological C-sequestration and enhanced production of oil and natural gas. The behavior of CO2, and CH4 are less well understood than that of H2O. This paper presents the results of a computational modeling study of the partitioning of CO2 and CH4 between bulk fluid and nano- and meso-pores bounded by the common clay mineral montmorillonite. The calculations were done at 323 K and a total fluid pressure of 124 bars using a novel approach (constant reservoir composition molecular dynamics, CRC-MD) that uses bias forces to maintain a constant composition in the fluid external to the pore. This purely MD approach overcomes the difficulties in making stochastic particle insertion-deletion moves in dense fluids encountered in grand canonical Monte Carlo and related hybrid approaches. The results show that both the basal siloxane surfaces and protonated broken edge surfaces of montmorillonite both prefer CO2 relative to CH4 suggesting that methods of enhanced oil and gas production using CO2 will readily displace CH4 from such pores. This preference for CO2 is due to its preferred interaction with the surfaces and extends to approximately 20 Ã… from them.
For decades, silicon has been the chief technological semiconducting material of modern microelectronics and has a strong influence on all aspects of the society. Applications of Si-based optoelectronic devices are limited to the visible and near infrared (IR) ranges. For photons with an energy less than 1.12 eV, silicon is almost transparent. The expansion of the Si absorption to shorter wavelengths of the IR range is of considerable interest for optoelectronic applications. By creating impurity states in Si, it is possible to cause sub-bandgap photon absorption. Herein, an elegant and effective technology of extending the photo-response of Si toward the IR range is presented. This approach is based on the use of Ag2S quantum dots (QDs) planted on the surface of Si to create impurity states in the Si bandgap. The specific sensitivity of the room temperature zero-bias Si_Ag2S detector is 1011 cm √Hz W−1 at 1.55 μm. Given the variety of available QDs and the ease of extending the photo-response of Si toward the IR range, these findings open a path toward future studies and development of Si detectors for technological applications. The current research at the interface of physics and chemistry is also of fundamental importance to the development of Si optoelectronics.