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The appearance of parametric resonance and the excitation of a longitudinal plasma wave in a system of coupled Josephson junctions with topologically trivial and nontrivial barriers have been demonstrated. The voltage at resonance as a function of the dissipation parameter has a minimum at which the parametric resonance condition changes from ωJ = 2ωLPWtoωJ = ωLPW, where is the Josephson frequency and ωLPW is the frequency of the formed longitudinal plasma wave. The position of this minimum for the system with nontrivial barriers is shifted from that for the system with trivial barriers. This shift can be used to identify the appearance of Majorana states.

In this chapter we focus on superconductivity and superconducting materials. We discuss the discovery of high-temperature (HTc) superconductors and provide an overview of HTc superconducting materials. We present the construction of four types of Josephson junction and derive the relations that describe the Josephson effect. We discuss the design of the classical electrochemical standards of direct voltage and standards with Josephson junctions. The parameters of the standards are compared, and the advantages of the quantum standards with Josephson junctions described. Also provided are the results of a comparison of the quantum standard at the Polish Central Office of Measures with the BIPM standard. We present the design of two types of alternating-voltage standards with Josephson junctions: binary divided junction arrays and pulse-driven junction arrays. Also presented are the principles of operation of the memory cell and flip-flop, basic components in digital cryoelectronics.

We begin this chapter with a brief presentation of the theory of single electron tunneling (SET) through a potential barrier. The conditions necessary for the observation and registration of this effect include a low temperature of a few kelvins and a small-sized sample. Low temperature will reduce the thermal energy that could interfere with the tunneling process. A small size of the tunneling junction is necessary to ensure its low electric capacitance. Further in this chapter we describe the basic electronic systems using SET: the SETT transistor, the electron pump, and the turnstile device. We discuss the attempts to construct a direct-current standard with SET junctions and explain why the results are unsatisfactory. We also describe two SET systems of more practical importance: the electron-counting capacitance standard (ECCS) and the Coulomb blockade thermometer (CBT).

This chapter is devoted to the new, revised SI system, eventually accepted in 2018, and to the phases of its conception and creation. In this context we present the need for improvement of the system of units, and the international efforts to create a new system. There was unanimous consent in the metrological community that a new system of measurement should be defined on the basis of fundamental physical and atomic constants, as it has been put forward for 180 years, since the first proposals by K. Gauss and J. Clerk Maxwell. We discuss the proposed redefinition of four SI units: kilogram, ampere, kelvin and mole. We present the particular importance of the new definition of the kilogram and the difficulties encountered in the development of a quantum standard of the unit of mass. The practical realization (mise en pratique) of any unit generally means establishment the value and associated uncertainty of a quantity of the unit of the same kind. Mise en pratique for realization of the units of the SI were prepared by the Consultive Committees of the CIPM. They are presented in Sects. 3.5–3.8.

This chapter opens with a presentation of the classical Drude theory of electrical conduction and a theory proposed by Landauer. Based on the assumption that electrical conduction can be modeled as transfer of electrons between two electron reservoirs, the Landauer theory proves to describe particularly well the electrical resistance in nanoscale conductors, i.e., in nanostructures. Surprisingly, this theory implies that the conductance (and resistance) of a nanostructure is independent of its material and temperature, and only depends on the dimensions of the sample, changing in a stepwise manner with a step of h/2e 2 representing the conductance quantum. The quantization of electrical and thermal conductance in nanostructures has been verified experimentally. Conductance quantization in nanostructures is used in the analysis of large-scale integration circuits, as required by the currently used 14 nm technology and future technologies.

This chapter outlines the history of quantum mechanics and presents its fundamental formulas: the Schrodinger equation with the interpretation of the wave function, the Pauli exclusion principle, and the Heisenberg uncertainty principle. The latter is illustrated with sample numerical calculations. We briefly discuss the application of quantum effects in metrology, and present and compare the limits of accuracy and resolution of classical and quantum standards. Prospects for a new system of units are discussed as well.

This chapter begins with a brief overview of four global satellite systems for navigation and positioning, GPS, GLONASS, Beidou and Galileo (under development), and point out the differences between them. We have a cursory look at two regional navigation systems, the Indian NAVIC, and the Japanese QZSS. Most important applications of positioning systems are presented. There are navigation for cars, ships, airplanes and even ordinary pedestrians in the city or in the countryside, dissemination of time scale and search and rescue services. For high accurate metrology crucial is dissemination (distribution) of a precise time scale. All global navigation systems offer the function of dissemination of time scale. Important function of GNSS.

This chapter opens with a presentation of the classical Drude theory of electrical conduction and a theory proposed by Landauer. Based on the assumption that electrical conduction can be modeled as transfer of electrons between two electron reservoirs, the Landauer theory proves to describe particularly well the electrical resistance in nanoscale conductors, i.e., in nanostructures. Surprisingly, this theory implies that the conductance (and resistance) of a nanostructure is independent of its material and temperature, and only depends on the dimensions of the sample, changing in a stepwise manner with a step of h/2e 2 representing the conductance quantum. The quantization of electrical and thermal conductance in nanostructures has been verified experimentally. Conductance quantization in nanostructures is used in the analysis of large-scale integration circuits, as required by the currently used 14 nm technology and future technologies.

We propose to use measurements of electrical resistance for estimation of the geometric dimensions of nanostructures made of conductive materials. Transistors, resistors and conductive paths inside integrated circuits are fabricated in a form of thin films of progressively smaller size. At present (2017) microprocessors of fabrication technology of 10 nm have been manufactured. The technology of 7 nm will be implemented next year and the technology of 5 nm is expected in 10 years. The dimension of 10 or 5 nm refers to the length of a gate of a MOSFET transistor inside the chip. For the next generation of nanostructures, the 3D nanostructures, their scaling will be continued and measurements of them will be also necessary.

In the chapter, problems of measurements of electrical conductance in nanostructures, particularly in nanowires, are considered. According to the Landauer theory of electrical conductance, the conductance of nanostructure is quantized. The electrical conductance of nanowires was measured in a simple experimental system. Investigations have been performed in air at room temperature measuring the conductance between two vibrating metal wires with standard oscilloscope. Conductance quantization in units of G0 = 2e2/h up to five quanta of conductance has been observed for nanowires formed in many metals. The explanation of these universal phenomena is the formation of a nanometer-sized wire (nanowire) between macroscopic metallic contacts which induced, due to theory proposed by Landauer, the quantization of conductance. Estimation of geometrical dimensions of nanostructures on basis of measurements of their electrical conductance is proposed in this paper.

In this chapter we discuss the efforts to redefine the unit of mass, the kilogram, and to develop a standard adequate to the new definition. The kilogram is likely to be redefined in relation to Planck’s constant. The work in progress discussed in this chapter aims to determine Planck’s constant by means of a watt balance and the Avogadro constant by counting the number of atoms in a mass standard of monocrystalline silicon 28Si (XRCD method). For the new definition to be adopted the uncertainty of the results of measurements performed by three different teams should be better than 5 × 10−8 and the results obtained by different methods should agree. Apart from the two methods mentioned above, we discuss the development of a mass standard based on the accumulation of heavy metal ions of gold (197Au) and bismuth (209Bi).

This chapter begins with a discussion of the evolution of the international definition of the meter, from that adopted by the Meter Convention in 1875 to the current definition relating the unit of length with the speed of light. We present three methods for the realization of the definition of the meter as recommended by the International Committee for Weights and Measures (CIPM). We discuss the design, operation and parameters of the iodine-stabilized helium-neon (He-Ne) laser with a wavelength of 633 nm, the most important device in metrology of length. We provide and discuss a table of sources of reference radiation other than the He-Ne laser recommended by CIPM. We also provide a brief overview of three global satellite systems for navigation and positioning, GPS, GLONASS and Galileo (under development), and point out the differences between them. Finally, we have a cursory look at three regional navigation systems, the Chinese BeiDou, the Indian IRNSS, and the Japanese QZSS.

This chapter is devoted to the assessment of the quality of the standards and the present SI system of measurement. In this context we present the need for improvement of the system of units, and the international efforts to create a new system. There is unanimous consent in the metrological community that a new system of measurement should be defined on the basis of fundamental physical and atomic constants, as it has been put forward for 180 years, since the first proposals by K. Gauss and J. Clerk Maxwell. We discuss the proposed redefinition of four SI units: kilogram, ampere, kelvin and mole. We present the particular importance of the new definition of the kilogram and the difficulties encountered in the development of a quantum standard of the unit of mass.

This chapter presents atomic frequency standards with high-stability frequency of oscillations. Also discussed is the Allan variance used for measuring the frequency fluctuations in such standards. We present the design of the 9.2 GHz cesium standard, which is presently the most important atomic standard. We discuss the directions of development and the metrological parameters of cesium atomic standards: more complicated and expensive, but providing better accuracy cesium fountain standards, and much cheaper miniature cesium standards with the size of a matchbox. Also discussed are other frequency standards: hydrogen masers, rubidium standards and the currently implemented standards with a visible wavelength. Optical frequency standards are potentially 105 times more stable than the cesium standard, though at present their actual stability is only 10 times higher. Together with the optical frequency standards we discuss the optical comb, used for mapping frequencies of the order of 1014 Hz to MHz frequencies. Also discussed are the major time scales, the International Atomic Time (TAI) and the Coordinated Universal Time (UTC), as well as the role of satellite navigation systems (GPS, GLONASS, BeiDou) in the dissemination of the standard time signal.

This chapter presents scanning probe microscopy and the most important microscopes using this technique. Historically the first of these devices, the scanning tunneling microscope (STM) is used for atomic-scale imaging of the surface of samples of conducting materials. The STM is an inestimable instrument for research in solid state physics, quantum chemistry and molecular biology. Its operation is based on the conversion of the distance between its tip and the studied surface into electric current. Another question is the control of the position of the scanning tip and the recording of data for generating a map of the studied surface. The experience acquired in the construction of the STM was of much use in the development of other types of scanning microscopes. In this chapter we discuss also the atomic force microscope (AFM), electrostatic force microscope (EFM), scanning thermal microscope (SThM) and scanning near-field optical microscope (SNOM). We also present a wide range of current and prospective applications of scanning microscopes.

In this chapter we discuss the history of measurements and standards across centuries, presenting the development of standards of units of length, time, temperature and electrical quantities from historical to contemporary units. Measurements of temperature and temperature scales, to which this book does not devote a separate chapter, are discussed at some length here. We also present the development of systems of measurement, from an early Chinese system consisting of units of length, volume and mass, through the first international systems to the SI system. The SI system is defined along with its seven base units: meter, kilogram, second, ampere, kelvin, candela and mole. We refer to the Meter Convention as the starting point of a wide international cooperation aimed at the unification of measurement units and the preservation of quality of standards. We discuss the organization of the international and national measurement services, and the role of the International Bureau of Weights and Measures (BIPM) and the national metrological institutes (NMIs).

This chapter presents the principles of operation and design of superconducting quantum interference devices, known under the acronym SQUID. RF-SQUIDs, which have a single Josephson junction in a closed magnetic circuit and are biased with radio-frequency signal, are discussed with their parameters provided. At much greater length we discuss DC-SQUIDs, which have two Josephson junctions and are biased with direct current. The equation describing the conversion of the magnetic flux to the output voltage is derived for both the RF- and DC-SQUIDs. We analyze the energy resolution of SQUIDs, citing the record resolution of the DC-SQUID, equal to 0.5h. We provide many examples of SQUID-based measurement systems, including systems for biomagnetic studies, non-destructive evaluation (NDE) systems and noise thermometers for the measurement of very low temperatures.

Resonance phenomena in a model of intrinsic Josephson junctions shunted by LC-elements (L-inductance, C-capacitance) are studied. The phase dynamics and IV-characteristics are investigated in detail when the Josephson frequency approaches the frequency of the resonance circuit. A realization of parametric resonance through the excitation of a longitudinal plasma wave, within the bias current interval corresponding to the resonance circuit branch, is demonstrated. It is found that the temporal dependence of the total voltage of the stack, and the voltage measured across the shunt capacitor, reflect the charging of superconducting layers, a phenomenon which might be useful as a means of detecting such charging experimentally. Thus, based on the voltage dynamics, a novel method for the determination of charging in the superconducting layers of coupled Josephson junctions is proposed. A demonstration and discussion of the influence of external electromagnetic radiation on the IV-characteristics and charge-time dependence is given. Over certain parameter ranges the radiation causes an interesting new type of temporal splitting in the charge-time oscillations within the superconducting layers.

The BF 245 transistors were investigated in the temperature range from300 K to 1.4 K. The transistors work satisfactorily in this temperature range. Some of the investigated transistors were used in a one-stage electronic amplifier. The amplifier operated properly in the whole temperature range between 300 K and 1.4 K . The voltage gain of the amplifier was 3 V/V in the temperature range from 4.2 K to 1.4 K. The dissipated power of the amplifier was 40 mW. Three thermal cycles 300 K … 1 . 4 K … 300 K were performed. The performance of the amplifier was not altered after the thermal cycles were completed.

The possibility or even necessity of revising definit ions of some of the base units of the present SI has been discussed over the past 15 years. The last General C onference of Weights and Measures (2007) recommended to redefine the kilogram, the ampere, the kelvin, and th e mole using fixed values of the fundamental constants by the time of the next General Conference in 2011. This paper is a review of proposals of new definitions of units of mentioned quantities and arguments voting for part icular variants of definitions. Most relevant papers for this review have been published by Me trologia, the international journal appointed at the BIPM, an d many other useful pieces of information are available on www pages of the BIPM. The author notes that not only new definitions have been discussed but as well as the se t of the base units of the SI. It means a replacement of the ampere by the volt or the kelvin by the joule. Decisions concerning new definitions are not made and the discussions are still open. Ke ywords: SI system, base units, quantum standards.

The paper describes system for monitoring important physical quantities of the environment, including meteorological information as well. Natural environment and technical infrastructure (artificial environment) can be consider like a metastable physical system. Monitoring system for environment consists of: sensors and optical cameras, communication interface and system controller with data acquisition, data processing, storage and presentation. Monitoring systems are always distributed systems. Communication channels (electrical and optical cables and wireless channels) play important role in dynamics and reliability of a monitoring system. For users it is necessary to know the dynamics of the whole monitoring system. Monitoring of infrastructure (road, power and communications networks, sewage systems) is as important as natural environment monitoring for population security.

We have observed conductance quantization of macroscopic metallic contacts in a circuit with a mechanical relay and LC circuit. The investigation has been performed outdoors at room temperature, and it was focused on measuring the conductance between two vibrating metal wires. Transient states of the current in a circuit are also described in the paper, this description includes a contact with quantized conductance. We can assume the occurance of oscillations in an electrical circuit with a relay, due to existence of conductance quantization at relay contacts. When designing a circuit with transmitter, one should take into account the fact that the resistance of its contacts together with the capacity and inductance of the whole system may lead to the appearance of oscillations.

The chapter describes a study of a distributed system for monitoring important physical and chemical quantities of the environment, including meteorological information. The monitoring system consists of: measurement stations with sensors, communication interface, and system controller with data acquisition, data processing, storage, and presentation. From a technical point of view, it is necessary to know the dynamics of the whole monitoring system and its reliability. The sensors measure air and water quality and other parameters like water levels. Monitoring of infrastructure (road, power and communications networks, sewage systems) is as important as natural environment monitoring for population security. We present a traffic monitoring system as an example of infrastructure monitoring.

Two parallel stacks of coupled Josephson junctions (JJs) are investigated to clarify the physics of transitions between the rotating and oscillating states and their effect on the IV-characteristics of the system. The detailed study of phase dynamics and bias dependence of the superconducting and diffusion currents allows one to explain all features of simulated IV-characteristics and demonstrate the correspondence in their behavior. The coupling between JJ in the stacks leads to the branching of IV-characteristics and a decrease in the hysteretic region. The crucial role of the diffusion current in the formation of the IV-characteristic of the parallel stacks of coupled JJs is demonstrated. We discuss the effect of symmetry in a number of junctions in the stacks and show a decrease of the branching in the symmetrical stacks. The observed effects might be useful for development of superconducting electronic devices based on intrinsic JJs.

We study the phase dynamics and the resonance features of coupled Josephson junctions in layered superconductors and their manifestations in the current- voltage characteristics and temporal dependence of the electric charge in the superconducting layers. Results on the effect of the external radiation and shunting of the stack of Josephson junctions by LC-elements are presented. We discuss the ideas concerning the experimental observation of these resonances.

In this paper we discuss some physical limits for scaling of devices and conducting paths inside of semiconductor integrated circuits (ICs). Since 40 years only a semiconductor technology, mostly the CMOS and the TTL technologies, are used for fabrication of integrated circuits in the industrial scale. Miniaturization of electronic devices in integrated circuits has technological limits and physical limits as well. In 2010 best parameters of commercial ICs shown the dual-core Intel Core i5-670 processor manufactured in the technology of 32 nm. Its clock frequency in turbo mode is 3.73 GHz. A forecast of the development of the semiconductor industry (ITRS 2009) predicts that sizes of electronic devices in ICs circuits will be smaller than 10 nm in the next 10 years. The physical gate length in a MOSFET will even amount 7 nm in the year 2024. At least 5 physical effects should be taken into account if we discuss limits of scaling of integrated circuits.

In the paper problems of electron transport in mesoscopic structures and nanostructures are considered. The electrical conductance of nanowires was measured in a simple experimental system. Investigations have been performed in air at room temperature measuring the conductance between two vibrating metal wires with standard oscilloscope. Conductance quantization in units of G0 = 2e2/h = (12.9 kΩ)-1 up to five quanta of conductance has been observed for nanowires formed in many metals. The explanation of this universal phenomena is the formation of a nanometer-sized wire (nanowire) between macroscopic metallic contacts which induced, due to theory proposed by Landauer, the quantization of conductance. Thermal problems in nanowires are also discussed in the paper.

The ability to work at low temperatures as well as the noise parameters of silicon junction field effect transistors were investigated. Some properties of the transistors at low temperatures result from self-heating of the silicon crystal of the transistor. The noise voltage of a JFET at low temperatures is determined by the temperature of its crystal, which is much higher than the ambient temperature of the transistor.