The quantum phase slip phenomenon in superconducting nanowires with a low-Ohmic environment
In a number of recent experiments it has been demonstrated that in ultra-narrow
superconducting channels quantum fluctuations of the order parameter, alternatively called
quantum phase slips, are responsible for the finite resistance well below the critical
temperature. Acceptable agreement between those experiments and the models describing
quantum fluctuations in quasi-one-dimensional superconductors has been established.
However, the very concept of phase slip is justified when these fluctuations are relatively rare
events, meaning that the effective resistance of the system should be much smaller than the
normal state equivalent. In this paper we study the limit of the strong quantum fluctuations
where the existing models are not applicable. In the particular case of ultra-thin titanium
nanowires, it is demonstrated that below the expected critical temperature the resistance does
not demonstrate any trend towards the conventional for a superconductor zero-resistivity state
even at negligibly small measuring currents. The application of a small magnetic field leads to
an unusual negative magnetoresistance, which becomes more pronounced at lower
temperatures. The origin of the negative magnetoresistance effect is not clear.
I discuss the ontological nature and heuristic value of psychedelic experience. I argue that psychedelic phenomena may manifest the activity of certain mental formations and brain mechanisms that otherwise remain hidden. Thus, psychedelic phenomena can be heuristic tools and intriguing objects of the scientific study. I consider two types of psychedelic phenomena in particular. The first is the moral cleansing that may accompany a psychedelic trip. The second is the appearance of visual and auditory hallucinations. I establish a unified explanatory ground for the phenomena that are commonly viewed as distinct in their genesis. I explain both types of phenomena as products of the amplified imaginative ability of the brain under a substance’s influence. I suggest that the activation of imagination causes an increased empathy and thus accentuates moral feelings. I propose the hypothesis that hallucinations are mental objects of a quantum nature. I argue that no ontologically separate reality stands behind psychedelic visions.
Heat pipes application in nanotechnological equipment is considered on examples of probe movement manipulators. Approaches to improvements of manipulators for effective heat extraction from operating area are shown.
In the original paper the affiliation of A.S. Aladyshkina was indicated incorrectly. The correct affiliations of all authors are as follows:
A.Yu. Aladyshkin., (1) I.M. Nefedov(1), A.S. Aladyshkina(2) and I.A. Shereshevskii(1). (1) Institute for Physics of Microstructures, Russian Academy of Sciences, GSP.105, Nizhny Novgorod 603950, Russia (2) National Research University Higher School of Economics, 25/12 Bolshaja Pecherskaja Ulitsa, Nizhny Novgorod 603155, Russia
A new approach is proposed to solve the quantum evolution problem for a system with an arbitrary number of coupled optical parametric processes. Our method is based on the canonical transformations which define the evolution of the system in the Heisenberg picture. This theory overcomes the difficulties arising in the Wei–Norman method. The application of the approach developed is illustrated with the example of generation of a three-mode entangled light field.
The dynamics of a two-component Davydov-Scott (DS) soliton with a small mismatch of the initial location or velocity of the high-frequency (HF) component was investigated within the framework of the Zakharov-type system of two coupled equations for the HF and low-frequency (LF) fields. In this system, the HF field is described by the linear Schrödinger equation with the potential generated by the LF component varying in time and space. The LF component in this system is described by the Korteweg-de Vries equation with a term of quadratic influence of the HF field on the LF field. The frequency of the DS soliton`s component oscillation was found analytically using the balance equation. The perturbed DS soliton was shown to be stable. The analytical results were confirmed by numerical simulations.
By using superconducting quantum interference device (SQUID) magnetometry, we investigated anisotropic high-field (H less than or similar to 7T) low-temperature (10 K) magnetization response of inhomogeneous nanoisland FeNi films grown by rf sputtering deposition on Sitall (TiO2) glass substrates. In the grown FeNi films, the FeNi layer nominal thickness varied from 0.6 to 2.5 nm, across the percolation transition at the d(c) similar or equal to 1.8 nm. We discovered that, beyond conventional spin-magnetism of Fe21Ni79 permalloy, the extracted out-of-plane magnetization response of the nanoisland FeNi films is not saturated in the range of investigated magnetic fields and exhibits paramagnetic-like behavior. We found that the anomalous out-of-plane magnetization response exhibits an escalating slope with increase in the nominal film thickness from 0.6 to 1.1 nm, however, it decreases with further increase in the film thickness, and then practically vanishes on approaching the FeNi film percolation threshold. At the same time, the in-plane response demonstrates saturation behavior above 1.5-2T, competing with anomalously large diamagnetic-like response, which becomes pronounced at high magnetic fields. It is possible that the supported-metal interaction leads to the creation of a thin charge-transfer (CT) layer and a Schottky barrier at the FeNi film/Sitall (TiO2) interface. Then, in the system with nanoscale circular domains, the observed anomalous paramagnetic-like magnetization response can be associated with a large orbital moment of the localized electrons. In addition, the inhomogeneous nanoisland FeNi films can possess spontaneous ordering of toroidal moments, which can be either of orbital or spin origin. The system with toroidal inhomogeneity can lead to anomalously strong diamagnetic-like response. The observed magnetization response is determined by the interplay between the paramagnetic-and diamagnetic-like contributions.
Radiation conditions are described for various space regions, radiation-induced effects in spacecraft materials and equipment components are considered and information on theoretical, computational, and experimental methods for studying radiation effects are presented. The peculiarities of radiation effects on nanostructures and some problems related to modeling and radiation testing of such structures are considered.
This volume presents new results in the study and optimization of information transmission models in telecommunication networks using different approaches, mainly based on theiries of queueing systems and queueing networks .
The paper provides a number of proposed draft operational guidelines for technology measurement and includes a number of tentative technology definitions to be used for statistical purposes, principles for identification and classification of potentially growing technology areas, suggestions on the survey strategies and indicators. These are the key components of an internationally harmonized framework for collecting and interpreting technology data that would need to be further developed through a broader consultation process. A summary of definitions of technology already available in OECD manuals and the stocktaking results are provided in the Annex section.