Superconducting spin valve effect in Co/Pb/Co heterostructures with insulating interlayers

• Andrey A. Kamashev,
• Nadir N. Garif’yanov,
• Aidar A. Validov,
• Vladislav Kataev,
• Alexander S. Osin,
• Yakov V. Fominov and
• Ilgiz A. Garifullin

Beilstein J. Nanotechnol. 2024, 15, 457–464, doi:10.3762/bjnano.15.41

• ][10]. The interest in these structures is due to the possibility to observe and exploit the reciprocal influence of superconductivity (S) and ferromagnetism (F) on each other when they are put into a close contact [11][12][13][14][15][16][17]. Moreover, SSV structures appear as promising devices for

• structure based on the control of the average exchange field acting on the S layer by changing the mutual orientation of the magnetization vectors of the F layers and, thus, suppressing superconductivity to a different degree. Typically, the superconducting transition temperature Tc of the SSV is minimal

• demonstrated by Deutscher and Meunier in 1969 [40]. The idea behind the oxidation of the FeNi and Ni layers was to slightly weaken the S/F proximity effect such that the superconductivity in the In layer could not be completely destroyed by the exchange field of the F layers. The authors noted that the thin

Design, fabrication, and characterization of kinetic-inductive force sensors for scanning probe applications

• August K. Roos,
• Ermes Scarano,
• Elisabet K. Arvidsson,
• Erik Holmgren and
• David B. Haviland

Beilstein J. Nanotechnol. 2024, 15, 242–255, doi:10.3762/bjnano.15.23

• ; kinetic inductance; optomechanics; superconductivity; Introduction Cavity optomechanics [1] deals with the detection and manipulation of massive “test objects” at the fundamental limits imposed by quantum physics [2]. By detecting the motion of the test object, we can sense an external force, for example

Exploring disorder correlations in superconducting systems: spectroscopic insights and matrix element effects

• Vyacheslav D. Neverov,
• Alexander E. Lukyanov,
• Andrey V. Krasavin,
• Alexei Vagov,
• Boris G. Lvov and
• Mihail D. Croitoru

Beilstein J. Nanotechnol. 2024, 15, 199–206, doi:10.3762/bjnano.15.19

• Física, Centro de Ciências Exatas e da Natureza,Universidade Federal de Pernambuco, Recife, Pernambuco, 50740-560, Brasil 10.3762/bjnano.15.19 Abstract Understanding the intricate interplay between disorder and superconductivity has become a key area of research in condensed matter physics, with

• profound implications for materials science. Recent studies have shown that spatial correlations of disorder potential can improve superconductivity, prompting a re-evaluation of some theoretical models. This paper explores the influence of disorder correlations on the fundamental properties of

• coupling constant and their impact on the localization length. Our findings offer valuable insights into the role of disorder correlations in shaping the behavior of superconducting materials. Keywords: disorder; spatial correlations; superconductivity; Introduction In contemporary quantum physics

Graphene removal by water-assisted focused electron-beam-induced etching – unveiling the dose and dwell time impact on the etch profile and topographical changes in SiO₂ substrates

• Aleksandra Szkudlarek,
• Jan M. Michalik,
• Inés Serrano-Esparza,
• Zdeněk Nováček,
• Veronika Novotná,
• Piotr Ozga,
• Czesław Kapusta and
• José María De Teresa

Beilstein J. Nanotechnol. 2024, 15, 190–198, doi:10.3762/bjnano.15.18

• unconventional strong electron–electron interactions, present in superlattices formed in twisted bilayered and trilayered graphene, led to the emergence of a new field called “twistronics” – just to highlight recent remarkable discoveries such as superconductivity [2][3], topological phases [4][5], and the

Spin dynamics in superconductor/ferromagnetic insulator hybrid structures with precessing magnetization

• Yaroslav V. Turkin and
• Nataliya Pugach

Beilstein J. Nanotechnol. 2023, 14, 233–239, doi:10.3762/bjnano.14.22

• superconductivity, as it has been done in the pioneering work by Houzet [32]. Two-time quasiclassical Green’s functions have the following structure [28]: The time-periodicity condition allows for the representation of spin current and induced magnetization as time-harmonic variables: where t = (t1 + t2)/2 is the

• magnetization precession and proximity effect can suppress superconductivity at the interface causing an increasing number of quasiparticles. To explore the spin dynamics of the quasiparticles more deeply, let us investigate spin components of the electron block of the distribution function. Spin polarization

Cooper pair splitting controlled by a temperature gradient

• Dmitry S. Golubev and
• Andrei D. Zaikin

Beilstein J. Nanotechnol. 2023, 14, 61–67, doi:10.3762/bjnano.14.7

• -superconducting multiterminal structures cross correlations of current noise in different terminals always remain negative [19], such cross correlations may become positive in the presence of superconductivity due to the process of CAR. This conclusion was initially reached theoretically in the limit of low

Upper critical magnetic field in NbRe and NbReN micrometric strips

• Zahra Makhdoumi Kakhaki,
• Antonio Leo,
• Federico Chianese,
• Loredana Parlato,
• Giovanni Piero Pepe,
• Angela Nigro,
• Carla Cirillo and
• Carmine Attanasio

Beilstein J. Nanotechnol. 2023, 14, 45–51, doi:10.3762/bjnano.14.5

• and nodal superconductivity, helical vortex states, as well as non-trivial topological effects. Moreover, large values of the upper critical magnetic field have been reported in these materials. Here, we focus on the study of the temperature dependence of the perpendicular magnetic field of NbRe and

• the robustness of the superconductivity in a specific material. For a standard BCS s-wave type-II superconductor, Werthamer, Helfand, and Hohenberg (WHH) have calculated the temperature dependence of the critical field [19]. In this model, two mechanisms are responsible for the breaking of the

• superconductivity and both contribute to the behavior of Hc2(T), namely the orbital and the paramagnetic effect. While the former is due to the Lorentz force acting on electrons of the Cooper pairs with opposite momentum, the latter is related to splitting of the spin-singlet pairs because of the Zeeman effect

The influence of structure and local structural defects on the magnetic properties of cobalt nanofilms

• Alexander Vakhrushev,
• Aleksey Fedotov,
• Olesya Severyukhina and
• Anatolie Sidorenko

Beilstein J. Nanotechnol. 2023, 14, 23–33, doi:10.3762/bjnano.14.3

• working volume during change of aggregate states, and is actively implemented as a highly efficient and energy-saving technology in the field of construction [9] and solar energy [10]. Phase transformations occupy an important position in the theories of superconductivity and ferromagnetic alloys. These

• temperature for pure metal equal to 9.25 K. In superconductors, including niobium, due to the Meissner effect, the phenomenon of complete or partial ejection of the magnetic field from the material volume occurs [48][49]. In the superconductivity mode, which is the mode of greatest interest for the magnetic

• magnetic properties of the spin nanocomposite, whose appearance and structure are demonstrated in Figure 3а. To investigate the magnetic properties of nanomaterials, the substrate temperature was set in the range of niobium nanofilm superconductivity mode operation at 5 K. Regarding the problem of nanofilm

Induced electric conductivity in organic polymers

• Konstantin Y. Arutyunov,
• Anatoli S. Gurski,
• Vladimir V. Artemov,
• Alexander L. Vasiliev,
• Azat R. Yusupov,
• Danfis D. Karamov and
• Alexei N. Lachinov

Beilstein J. Nanotechnol. 2022, 13, 1551–1557, doi:10.3762/bjnano.13.128

• currents limited by the space charge. At temperatures below ≈8 K, a number of samples exhibit features that can be explained by the effect of induced superconductivity in a thin film of conducting polymer enclosed between two massive superconductors (lead). Keywords: conducting polymer; superconductivity

• several nm, while in our case superconductivity in Pb–PDP–Pb sandwiches manifests itself at polymer thicknesses up to 350 nm. Hence, it can be assumed that the dependencies in Figure 4 can be explained by the effect of induced superconductivity in a thin film of conducting polymer enclosed between two

• massive superconductors (lead). The substantiation of this assertion requires further verification. In the near future, experiments are planned on planar heterostructures, where superconductivity, if observed, cannot be explained by trivial metallic shortcuts. Conclusion R(T), V(I) and dV/dI(V

Density of states in the presence of spin-dependent scattering in SF bilayers: a numerical and analytical approach

• Tairzhan Karabassov,
• Valeriia D. Pashkovskaia,
• Nikita A. Parkhomenko,
• Anastasia V. Guravova,
• Elena A. Kazakova,
• Boris G. Lvov,
• Alexander A. Golubov and
• Andrey S. Vasenko

Beilstein J. Nanotechnol. 2022, 13, 1418–1431, doi:10.3762/bjnano.13.117

• behavior of DOS dependencies on magnetic and spin–orbit scattering times is discussed. Keywords: density of states; Josephson junctions; proximity effect; superconductivity; superconductor/ferromagnet hybrid nanostructures; Introduction It is well-known that superconductivity can be induced in a non

• the diffusion constant in the normal metal and Tc is the transition temperature. When a superconductor S is combined with a ferromagnetic layer F, forming an SF bilayer, the superconductivity leaks into the ferromagnetic region over the characteristic length ξh = where Df is the diffusion constant in

• F layer and h is the exchange field in the ferromagnetic layer [1]. Not only superconductivity is substantially suppressed due to the exchange field, but also Cooper pairs gain a finite center of mass momentum, which leads to the oscillatory behavior of the Cooper pair wave function. These

Experimental and theoretical study of field-dependent spin splitting at ferromagnetic insulator–superconductor interfaces

• Peter Machon,
• Michael J. Wolf,
• Detlef Beckmann and
• Wolfgang Belzig

Beilstein J. Nanotechnol. 2022, 13, 682–688, doi:10.3762/bjnano.13.60

• field, we find good agreement between theory and experiment. The theory depends only on very few parameters, mostly specified by the experimental setup. We determine the effective spin of the interface moments as J ≈ 0.74ℏ. Keywords: circuit theory; magnetism; proximity effect; superconductivity

• superconductivity [7][8], the triplet proximity effect [9][10][11], and implementations of superconducting switches and spin valves based on either the singlet or triplet proximity effect [12][13][14][15][16][17][18]. Furthermore, the spin-dependent density of states due to the proximity of a magnetic insulator is

• boundaries between superconducting and normal state, with the superconducting phase at low temperature and small δφ. In general, the critical value δφc increases with decreasing ε’. For small ε’, spin mixing can no longer completely suppress superconductivity for T = 0 (note that the boundary conditions are

Tunable superconducting neurons for networks based on radial basis functions

• Andrey E. Schegolev,
• Nikolay V. Klenov,
• Sergey V. Bakurskiy,
• Igor I. Soloviev,
• Mikhail Yu. Kupriyanov,
• Maxim V. Tereshonok and
• Anatoli S. Sidorenko

Beilstein J. Nanotechnol. 2022, 13, 444–454, doi:10.3762/bjnano.13.37

• kinetic inductance. An example is a multilayer structure consisting of a superconducting “source”, a current-carrying layer and a spin valve with at least two magnetic layers with different thicknesses. The proposed tunable inductance does not require suppression of superconductivity in the source layer

Topographic signatures and manipulations of Fe atoms, CO molecules and NaCl islands on superconducting Pb(111)

• Carl Drechsel,
• Philipp D’Astolfo,
• Jung-Ching Liu,
• Thilo Glatzel,
• Rémy Pawlak and
• Ernst Meyer

Beilstein J. Nanotechnol. 2022, 13, 1–9, doi:10.3762/bjnano.13.1

• Carl Drechsel Philipp D'Astolfo Jung-Ching Liu Thilo Glatzel Remy Pawlak Ernst Meyer Department of Physics, Universität Basel, Klingelbergstrasse 82, 4056 Basel, Switzerland 10.3762/bjnano.13.1 Abstract Topological superconductivity emerging in one- or two-dimensional hybrid materials is

• of iron atoms on top of the prototypical Pb(111) superconducting surface. Keywords: carbon monoxide (CO); lateral manipulation; NaCl; scanning tunneling microscopy; superconductivity; Introduction The most exciting manifestation of topological superconductivity [1][2][3] is the Majorana zero mode

• (MZM), which has attracted a tremendous interest due to its non-Abelian quantum exchange statistics proposed as a key ingredient for topological quantum computing [4][5][6]. Topological superconductivity can intrinsically arise in the bulk of certain materials [7] or can be engineered at the interface

Design aspects of Bi₂Sr₂CaCu₂O_8+δ THz sources: optimization of thermal and radiative properties

• Mikhail M. Krasnov,
• Natalia D. Novikova,
• Roger Cattaneo,
• Alexey A. Kalenyuk and
• Vladimir M. Krasnov

Beilstein J. Nanotechnol. 2021, 12, 1392–1403, doi:10.3762/bjnano.12.103

• facilitating good impedance matching. This leads to more than an order of magnitude enhancement of the radiation power efficiency in whisker-based, compared to crystal-based, devices. These results are in good agreement with presented experimental data. Keywords: high-temperature superconductivity; Josephson

In situ transport characterization of magnetic states in Nb/Co superconductor/ferromagnet heterostructures

• Olena M. Kapran,
• Roman Morari,
• Taras Golod,
• Evgenii A. Borodianskyi,
• Vladimir Boian,
• Andrei Prepelita,
• Nikolay Klenov,
• Anatoli S. Sidorenko and
• Vladimir M. Krasnov

Beilstein J. Nanotechnol. 2021, 12, 913–923, doi:10.3762/bjnano.12.68

• computing; devices exploiting spin polarized transport or integrated magnetic field; spin-valve; superconducting multilayers; superconducting spintronics; Introduction Competition between spin-polarized ferromagnetism and spin-singlet superconductivity leads to a variety of interesting phenomena including

• affected by F-layer orientation. However, thin S′ spacers, Nb(6 and 8 nm), with a thickness comparable to the superconducting coherence length, ξS ≈ 10 nm, are strongly affected. Superconductivity in S′ layers is stronger in the AP state and is almost quenched in the outmost S′ layer in the P state. This

• is caused by subtractive (in the AP state) and additive (in the P state) influences of ferromagnetic exchange fields from neighbor F-layers, which are detrimental to the spin-singlet order in S′ [1][2][3][4][5][6][7][8]. Simulations in Figure 1c demonstrate the tunability of superconductivity in such

A review of defect engineering, ion implantation, and nanofabrication using the helium ion microscope

• Frances I. Allen

Beilstein J. Nanotechnol. 2021, 12, 633–664, doi:10.3762/bjnano.12.52

Kondo effects in small-bandgap carbon nanotube quantum dots

• Patryk Florków,
• Damian Krychowski and
• Stanisław Lipiński

Beilstein J. Nanotechnol. 2020, 11, 1873–1890, doi:10.3762/bjnano.11.169

• interference [13][14], Kondo physics [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29], spintronic effects [10][30][31][32], and induced superconductivity [33][34][35]. In the present paper, we are interested in the effects of strong correlations. As electrons are confined in fewer dimensions, the

Molecular dynamics modeling of the influence forming process parameters on the structure and morphology of a superconducting spin valve

• Alexander Vakhrushev,
• Aleksey Fedotov,
• Vladimir Boian,
• Roman Morari and
• Anatolie Sidorenko

Beilstein J. Nanotechnol. 2020, 11, 1776–1788, doi:10.3762/bjnano.11.160

• lead–iron, is small: TF ≈ 0.4. This reduces the probability of penetration of Cooper pairs from the superconductor into the ferromagnetic material and requires smaller thicknesses of superconducting layers in order to obtain a significant effect of ferromagnetism on superconductivity. In turn, the

Functional nanostructures for electronics, spintronics and sensors

• Anatolie S. Sidorenko

Beilstein J. Nanotechnol. 2020, 11, 1704–1706, doi:10.3762/bjnano.11.152

• superconductivity, triplet pairing and triplet spin-valve and memory effects – just to name some of the new phenomena that have been detected in layered S/F hybrid nanostructures [8]. Moreover, the detected effects are very promising for technical applications directed towards enhancing the storage capacity of

Controlling the proximity effect in a Co/Nb multilayer: the properties of electronic transport

• Sergey Bakurskiy,
• Mikhail Kupriyanov,
• Nikolay V. Klenov,
• Igor Soloviev,
• Andrey Schegolev,
• Roman Morari,
• Yury Khaydukov and
• Anatoli S. Sidorenko

Beilstein J. Nanotechnol. 2020, 11, 1336–1345, doi:10.3762/bjnano.11.118

• stacking periods. It is demonstrated that the magnetization switching results in modulation of superconductivity in the superlattice with a corresponding change in the kinetic inductance of the superconducting parts of the wire core, due to the inverse proximity effect. We argue that this effect

• which the thick S-bank acts as the source of induced superconductivity, is the simplest model of the 3D structure. Let us consider the applications that are possible due to the control over the order parameter in thin superconductor layers (s-layers) in such a structure. The simplest cell for the

• ). The main source of the superconductivity is the bulk semiconductor layer, while the thin s-layers only slightly support the pairing amplitude coming from the source. Figure 2b shows the spatial distributions of the anomalous Green’s function at the first (n = 0) Matsubara frequency, F1(x), for

Proximity effect in [Nb(1.5 nm)/Fe(x)]₁₀/Nb(50 nm) superconductor/ferromagnet heterostructures

• Yury Khaydukov,
• Sabine Pütter,
• Laura Guasco,
• Roman Morari,
• Gideok Kim,
• Thomas Keller,
• Anatolie Sidorenko and
• Bernhard Keimer

Beilstein J. Nanotechnol. 2020, 11, 1254–1263, doi:10.3762/bjnano.11.109

• the thickness of the Fe layer to x = 4 nm the intermediate phase disappears. We attribute the intermediate state to proximity induced non-homogeneous superconductivity in the structure. Keywords: ferromagnet; iron (Fe); mixed state; neutron reflectometry; niobium (Nb); proximity effects

• phenomena are π–Josephson junctions [4][5][6][7] with a π-phase difference of superconducting correlations between two neighboring interfaces, long-range triplet superconductivity [8][9][10][11][12][13][14][15][16] generated in S/F systems with a non-collinear (NC) magnetic configuration of the F system

• , and re-entrant superconductivity as evidence of nonuniform LOFF-states [17][18][19][20]. Apart from the interest in basic science, the proximity effect in S/F structures has great technological importance for the creation of spintronics devices, where the transport properties of the structure are

3D superconducting hollow nanowires with tailored diameters grown by focused He⁺ beam direct writing

• Rosa Córdoba,
• Alfonso Ibarra,
• Dominique Mailly,
• Isabel Guillamón,
• Hermann Suderow and
• José María De Teresa

Beilstein J. Nanotechnol. 2020, 11, 1198–1206, doi:10.3762/bjnano.11.104

• nanopipettes, as demonstrated in 3D reconstructions of electron tomography experiments. Finally, these 3D hollow NWs exhibit superconductivity below 6.8 K (Tc), as well as high upper critical magnetic fields µ0Hc2 ≈ 14.7 T, and large critical current densities Jc ≈ 0.15 MA/cm2. Results and Discussion Growth of

• . The presented methodology yields an advanced bottom-up approach for the fabrication of innovative 3D nano-architectures, in which nano-superconductivity may provide an advantage, for future electronic components, particularly for sensors, energy-storage components, and quantum computing. Experimental

Nonadiabatic superconductivity in a Li-intercalated hexagonal boron nitride bilayer

• Kamila A. Szewczyk,
• Izabela A. Domagalska,
• Artur P. Durajski and
• Radosław Szczęśniak

Beilstein J. Nanotechnol. 2020, 11, 1178–1189, doi:10.3762/bjnano.11.102

• percent. Keywords: critical temperature; electron–phonon interaction; Li-hBN bilayer; Li-intercalated hexagonal boron nitride (Li-hBN); nonadiabatic superconductivity; vertex corrections; Introduction Low-dimensional systems such as graphene [1][2][3][4][5], silicene [6], borophene [7][8], and

• graphene/hBN heterojunction devices allowed for the detection of the Hofstadter’s butterfly phenomenon [39][40]. In both layer and bulk form, hBN has a large bandgap energy, which makes it an insulator [13][41]. Therefore, for a long time this material was not associated with superconductivity. The

• observed in a system consisting of non-twisted bilayer graphene (BLG) and hexagonal boron nitride layers (hBN/BLG/hBN). The following characteristic temperatures were obtained: Tonset ≈ 50 K, T* ≈ 30 K, and TBKT = 14 K, which correspond the onset of superconductivity (90% of the total transition/normal

A Josephson junction based on a highly disordered superconductor/low-resistivity normal metal bilayer

• Pavel M. Marychev and
• Denis Yu. Vodolazov

Beilstein J. Nanotechnol. 2020, 11, 858–865, doi:10.3762/bjnano.11.71

• composed of a highly disordered superconductor (S) and a low-resistivity normal metal (N) with proximity-induced superconductivity. In such a junction, the N layer provides both a large concentration of phase in the weak link and good heat dissipation. We find that when the thickness of the S and the N

• obtain high noise immunity. But due to large critical current and bad heat dissipation their IVCs are hysteretic due to Joule heating () and the subsequent formation of a stable region with suppressed superconductivity (a so-called “hot spot”) at I > Ic [6][7][8][9]. At temperatures near the critical

• , ρS ≥ 100 μΩ·cm, and a thin normal metal layer with low resistivity, ρN ≥ 2 μΩ·cm. In such a thin SN bilayer the superconducting current mainly flows in the N layer (due to proximity-induced superconductivity and ρS/ρN ≫ 1), and the critical current of the SN bilayer may exceed the critical current of

High dynamic resistance elements based on a Josephson junction array

• Konstantin Yu. Arutyunov and
• Janne S. Lehtinen

Beilstein J. Nanotechnol. 2020, 11, 417–420, doi:10.3762/bjnano.11.32

• effect. Keywords: dynamic resistance; Josephson junction array; nanoelectronics; quantum phase slip; superconductivity; Ti nanowires; Introduction The field of modern nanoelectronics is facing stagnation with respect to further miniaturization, deviating from Moore’s law [1]. Typically, two main reason