Measurements of dichroic bow-tie antenna arrays with integrated cold-electron bolometers using YBCO oscillators

• Leonid S. Revin,
• Dmitry A. Pimanov,
• Alexander V. Chiginev,
• Anton V. Blagodatkin,
• Viktor O. Zbrozhek,
• Andrey V. Samartsev,
• Anastasia N. Orlova,
• Dmitry V. Masterov,
• Alexey E. Parafin,
• Victoria Yu. Safonova,
• Anna V. Gordeeva,
• Andrey L. Pankratov,
• Leonid S. Kuzmin,
• Anatolie S. Sidorenko,
• Silvia Masi and
• Paolo de Bernardis

Beilstein J. Nanotechnol. 2024, 15, 26–36, doi:10.3762/bjnano.15.3

• measured with YBCO Josephson Junction oscillators show narrow peaks at 205 GHz for the 210 GHz array and at 225 GHz for the 240 GHz array; the separation of these two frequency bands is clearly visible. The noise equivalent power level at an operating point in the current bias mode is 5 × 10−16 W/√Hz

• . Keywords: cosmic microwave background; B mode; cold-electron bolometer; dichroic antenna array; dipole bow-tie antenna; Josephson junction; LSPE; Introduction The cosmic microwave background (CMB) radiation contains a lot of information about origin and evolution of our universe. The temperature and

• efficient reduction of electron temperature down to 65 mK from a base temperature of 300 mK [22]. Here we present improved simulation results in comparison with [24] and the first results of fabrication and measurements, using YBa2Cu3O7 (YBCO) Josephson junction (JJ) oscillators, of a dichroic multiabsorber

A bifunctional superconducting cell as flux qubit and neuron

• Dmitrii S. Pashin,
• Pavel V. Pikunov,
• Marina V. Bastrakova,
• Andrey E. Schegolev,
• Nikolay V. Klenov and
• Igor I. Soloviev

Beilstein J. Nanotechnol. 2023, 14, 1116–1126, doi:10.3762/bjnano.14.92

• by the second term in Equation 1, wherein the effective coordinate is a phase of the Josephson junction, φ. The quantities Ec = and EJ = are the capacitive and the Josephson energy, respectively, determined by critical current Ic and the capacity C of the Josephson junction. A typical example of

• . The action time of the symmetric input flux to avoid Landau–Zener transitions is ∼100 ns for l = 2. The estimate was made with the characteristic parameters of a Josephson junction, that is, Ic = 50 nA and C = 6 fF. In contrast, it takes ∼30 ns for the transition from the ground state to the first

• ⟩ = bφin(t) − a⟨φ⟩ is the mean value of the current operator on the Josephson junction when the external flux changes relative to the mean phase of the contact ⟨φ⟩ = ⟨ψ(t)|φ|ψ(t)⟩. As shown in Figure 4a, the transfer characteristic of the parametron has a sigmoidal dependence. It is worth noting that this

A distributed active patch antenna model of a Josephson oscillator

• Vladimir M. Krasnov

Beilstein J. Nanotechnol. 2023, 14, 151–164, doi:10.3762/bjnano.14.16

• Vladimir M. Krasnov Department of Physics, Stockholm University, AlbaNova University Center, SE-10691 Stockholm, Sweden 10.3762/bjnano.14.16 Abstract Optimization of Josephson oscillators requires a quantitative understanding of their microwave properties. A Josephson junction has a geometry

• large impedance mismatch between a Josephson junction (JJ) and free space [10][16][17]. But there is no consensus about the value of the junction impedance: Is it very small [16] or, in contrast, very large [10]? At present, there is no clear understanding about what causes the impedance mismatch and

• Josephson junction. In the presence of a magnetic field and fluxons, the distribution of the oscillatory component of current is nonuniform. This nonuniformity is essential for operation of a Josephson flux-flow oscillator and determines the effective input resistance, which enables the coupling between the

Frontiers of nanoelectronics: intrinsic Josephson effect and prospects of superconducting spintronics

• Anatolie S. Sidorenko,
• Horst Hahn and
• Vladimir Krasnov

Beilstein J. Nanotechnol. 2023, 14, 79–82, doi:10.3762/bjnano.14.9

• a very high responsivity at 77 K (up to 9 kV/W), low noise equivalent power (NEP) of 3 × 10−13 W/Hz(1/2), and with a wide power dynamic range equal to 1 × 106 [18]. Integrating an aluminum Josephson junction, with a size of a few micrometers, operating as a single photon counter in the microwave

• magnetic proximity effect at a ferromagnetic–insulator–superconductor (FIS) interface was investigated through combined experimental and theoretical work [25]. Manifestations of nonlinear features in magnetic dynamics and current–voltage characteristics of the 0 Josephson junction in superconductor

Observation of collective excitation of surface plasmon resonances in large Josephson junction arrays

• Roger Cattaneo,
• Mikhail A. Galin and
• Vladimir M. Krasnov

Beilstein J. Nanotechnol. 2022, 13, 1578–1588, doi:10.3762/bjnano.13.132

• modes. Discussion Figure 8 summarizes our main results, that is, the observation of collective excitation of surface plasmon resonances by large Josephson junction arrays and the correlated enhancement of EMW emission. Figure 8a shows a close-up on the I–V characteristics from Figure 3b for the meander

Coherent amplification of radiation from two phase-locked Josephson junction arrays

• Mikhail A. Galin,
• Vladimir M. Krasnov,
• Ilya A. Shereshevsky,
• Nadezhda K. Vdovicheva and
• Vladislav V. Kurin

Beilstein J. Nanotechnol. 2022, 13, 1445–1457, doi:10.3762/bjnano.13.119

• , but also improved synchronization of junctions inside each array. Our conclusion is supported by numerical modelling. Keywords: coherent radiation; Josephson junction arrays; numerical modelling; single-strip line; synchronization; Introduction A Josephson junction (JJ) has the unique ability to

Nonlinear features of the superconductor–ferromagnet–superconductor φ₀ Josephson junction in the ferromagnetic resonance region

• Aliasghar Janalizadeh,
• Ilhom R. Rahmonov,
• Sara A. Abdelmoneim,
• Yury M. Shukrinov and
• Mohammad R. Kolahchi

Beilstein J. Nanotechnol. 2022, 13, 1155–1166, doi:10.3762/bjnano.13.97

• characteristics of a φ0 Josephson junction in the ferromagnetic resonance region. We show that at small values of the system parameters damping, spin–orbit interaction, and Josephson-to-magnetic energy ratio, the magnetic dynamics is reduced to the dynamics of a scalar Duffing oscillator driven by the Josephson

• different approximations. Finally, we demonstrate the negative differential resistance in the I–V characteristics and its correlation with the fold-over effect. Keywords: Duffing oscillator; Josephson junction; Landau–Lifshitz–Gilbert equation; Introduction The coupling of the superconducting phase

• pulse through the φ0 junction [3][9][10][11][12][13]. There are two features of Josephson junctions that come into play in our study. The first one is the broken inversion symmetry in the weak link of the Josephson junction when the link is magnetic, which introduces an extra phase in the current–phase

A superconducting adiabatic neuron in a quantum regime

• Marina V. Bastrakova,
• Dmitrii S. Pashin,
• Dmitriy A. Rybin,
• Andrey E. Schegolev,
• Nikolay V. Klenov,
• Igor I. Soloviev,
• Anastasiya A. Gorchavkina and
• Arkady M. Satanin

Beilstein J. Nanotechnol. 2022, 13, 653–665, doi:10.3762/bjnano.13.57

• obtained results indicate the conditions under which the neuron possesses the required sigmoid activation function. Keywords: Josephson junction; quantum neuron; quantum-classical neural networks; superconducting quantum interferometer; Introduction The implementation of machine learning algorithms is

• model and basic equations A single-junction superconducting interferometer with normalized inductance l, a Josephson junction without resistive shunting (JJ), an additional inductance la, and an output inductance lout (see Figure 1b) are the basis of the quantum neuron. This circuit has been presented

• in [46] when considering the classical mode of this system. Inductances are normalized to (2πIc/Φ0), where Ic is the critical current of the Josephson junction and Φ0 is the magnetic flux quantum. The inertial properties of the system are due to the junction capacitance, which, along with the

Approaching microwave photon sensitivity with Al Josephson junctions

• Andrey L. Pankratov,
• Anna V. Gordeeva,
• Leonid S. Revin,
• Dmitry A. Ladeynov,
• Anton A. Yablokov and
• Leonid S. Kuzmin

Beilstein J. Nanotechnol. 2022, 13, 582–589, doi:10.3762/bjnano.13.50

• , Russia Lobachevsky State University of Nizhny Novgorod, 603950, Nizhny Novgorod, Russia Chalmers University of Technology, 41296, Gothenburg, Sweden 10.3762/bjnano.13.50 Abstract Here, we experimentally test the applicability of an aluminium Josephson junction of a few micrometers size as a single

• of three and more photons, with a dark count time above 0.01 s. Keywords: Josephson junction; microwave photons; single photon counter; thermal activation; Introduction The development of a single photon counter (SPC) for microwave frequencies of tens of gigahertz has been required for several

• counter can be made on their basis. We use the metastable quasi-equilibrium state of a Josephson junction, which, at low temperatures, is stable enough for thermal fluctuations and quantum tunneling, but can be easily destroyed by absorption of a single photon. We demonstrate few-photon sensitivity of our

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

• the flux quantum Φ0; currents are normalized to the critical current of the Josephson junctions IC; inductances are normalized to the characteristic inductance 2πLIC/Φ0, times are normalised to the characteristic time tC = Φ0/(2πVC) (VC is the characteristic voltage of a Josephson junction). Equations

• operation of the cell (tRF up to 8000tC, where tC is the characteristic time for the Josephson junction). The dissipation during the operation of the Gauss-neuron remains small, which justifies classifying the proposed cell as adiabatic (Figure 4b). Realization of tunability: adjustable kinetic inductance

• left and right sides by 2: As the current through the Josephson junction has a form , Equation 11 gives us the first equation of motion (Equation 2) for the Gauss-neuron: Similar operations should be conducted for the difference between the second and third equations of the system in Equation 10: and

A broadband detector based on series YBCO grain boundary Josephson junctions

• Egor I. Glushkov,
• Alexander V. Chiginev,
• Leonid S. Kuzmin and
• Leonid S. Revin

Beilstein J. Nanotechnol. 2022, 13, 325–333, doi:10.3762/bjnano.13.27

• –frequency characteristic, beam pattern, and fraction of the absorbed power in each Josephson junction were investigated. Based on the obtained results, a numerical simulation of one-dimensional arrays was carried out. The dc characteristics of the detector were calculated, that is, current–voltage

• ; electromagnetic modeling; log-periodic antenna; RCSJ model; series Josephson junctions; YBaCuO Josephson junction; Introduction High-temperature superconducting (HTSC) Josephson junctions (JJs) have great potential as promising materials for creating high-frequency devices, such as microwave generators [1][2

• used as an element simulating the Josephson junction. It is known [17][24] that the impedance of the HTSC JJ is low, which makes the development of HTSC detectors and mixers difficult in comparison with low-temperature superconductor Josephson junction analogues. Figure 2 shows the dependence of the

Nonmonotonous temperature dependence of Shapiro steps in YBCO grain boundary junctions

• Leonid S. Revin,
• Dmitriy V. Masterov,
• Alexey E. Parafin,
• Sergey A. Pavlov and
• Andrey L. Pankratov

Beilstein J. Nanotechnol. 2021, 12, 1279–1285, doi:10.3762/bjnano.12.95

• ; Shapiro steps; temperature dependence; YBaCuO Josephson junction; Introduction High-temperature superconducting (HTSC) Josephson junctions (JJs) are of great interest since many physical properties can be observed in dynamics during the changing the temperature within a wide range from nitrogen

• that the simplest marker of the response level of a Josephson junction to microwave (MW) radiation is the magnitude of Shapiro steps. In the majority of works, an increase in sensitivity at low temperatures has been demonstrated [15][16][17], although a part of the papers indicate the receiver’s

• temperature. Figure 1 also shows the change in the Josephson junction characteristic length L/λJ, where is the Josephson penetration depth, which determines the size of a fluxon in the junction. Here μ0 is the vacuum permeability, Jc is the critical current density, and d = t + 2λL is the effective magnetic

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

• structures [45]. The performance of Josephson junctions in YBCO thin films fabricated using the HIM has been further evaluated in [46]. Cross-sectional STEM analysis of helium line irradiations of YBCO has shown that the crystallinity of the Josephson junction barriers is essentially preserved, highlighting

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

• for quantum computation. The behavior of nanosized superconductors as one-dimensional quantum oscillators [1], Josephson junction arrays [2], electronic transport devices [3][4][5][6][7], very small-scale devices [8][9], micrometer-scale coolers [10], or thermal and spin sensors [11][12] has been

Microwave photon detection by an Al Josephson junction

• Leonid S. Revin,
• Andrey L. Pankratov,
• Anna V. Gordeeva,
• Anton A. Yablokov,
• Igor V. Rakut,
• Victor O. Zbrozhek and
• Leonid S. Kuzmin

Beilstein J. Nanotechnol. 2020, 11, 960–965, doi:10.3762/bjnano.11.80

• Novgorod, Russia Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Russia Chalmers University of Technology, SE-41296 Gothenburg, Sweden 10.3762/bjnano.11.80 Abstract An aluminium Josephson junction (JJ), with a critical current suppressed by a factor of three compared with the maximal

• through the JJ is observed, which resembles the differentiation between N and N + 1 photon absorption. Keywords: aluminium; Josephson junction; microwaves; phase diffusion; photon counter; switching current distribution; Introduction Currently, an important problem is the creation of single-photon

• ]. For the lower-frequency range, a new class of single-microwave-photon detectors is needed. With regard to this, a current-biased Josephson junction (JJ) is of particular interest for applications as a threshold detector since its phase dynamics is altered even by a weak probe field. Rich dynamics of

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

• Pavel M. Marychev Denis Yu. Vodolazov Institute for Physics of Microstructures, Russian Academy of Sciences, Nizhny Novgorod, 603950, Russia 10.3762/bjnano.11.71 Abstract We calculate the current–phase relation (CPR) of a SN-S-SN Josephson junction based on a SN bilayer of variable thickness

• thickness dc where the N layer and, partially, the S layer are removed (Figure 1). We assume that in our system the current flows in the x direction, and in the y direction the system is uniform. To find the current–phase relation of such a SN-S-SN Josephson junction at all temperatures below Tc we solve a

• the superconductor S is equal to a). For these calculations we use a 1D Usadel equation. Results Current–phase relation of the SN-S-SN Josephson junction The function Is(q) in the SN bilayer may have one or two maxima depending on the value of dS (see Figure 2) or of dN (see Figure 3a in [15]). The

Epitaxial growth and superconducting properties of thin-film PdFe/VN and VN/PdFe bilayers on MgO(001) substrates

• Wael M. Mohammed,
• Igor V. Yanilkin,
• Amir I. Gumarov,
• Airat G. Kiiamov,
• Roman V. Yusupov and
• Lenar R. Tagirov

Beilstein J. Nanotechnol. 2020, 11, 807–813, doi:10.3762/bjnano.11.65

• ferromagnets to improve the operation characteristics of superconductor–ferromagnet–insulator heterojunctions for superconducting spintronics applications. For example, cubic superconducting MoNx, which is a Josephson junction technology material [4][5][46], exhibits a good epitaxial match with Pd1−xFex alloys

• small-scale computer based on superconducting logic and cryogenic memory that is energy-efficient, scalable and able to solve interesting problems”, opening prospects of reaching 100 PFLOPS/s with about 200 kW of electric power consumption including the cryogenic cooling. Niobium-based Josephson

• junction technology is currently implied to be used for the logics fabrication, however, hybrid Josephson junctions incorporating magnetic components are also considered for the mainframe computation components [9][14][15][16][17][18][19], and cache and main memories [8][20][21][22][23][24][25]. It is

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

• ), including superconducting systems based on the Josephson effect. It has been shown that physics behind a Josephson junction (JJ) is dual to a quantum phase-slip junction (QPSJ) [3], whereby the corresponding QPSJ-based qbit operation has also been demonstrated [4]. At the same time, the quantum dynamics of

Anomalous current–voltage characteristics of SFIFS Josephson junctions with weak ferromagnetic interlayers

• Tairzhan Karabassov,
• Anastasia V. Guravova,
• Aleksei Yu. Kuzin,
• Elena A. Kazakova,
• Shiro Kawabata,
• Boris G. Lvov and
• Andrey S. Vasenko

Beilstein J. Nanotechnol. 2020, 11, 252–262, doi:10.3762/bjnano.11.19

• characteristic of a SNINS Josephson junction with a characteristic peak at eV ≈ 2Δ (see Figure 5a, solid black line) [101]. With an increase of the exchange field h this peak becomes smeared (see Figure 5b–d, solid black line). Increasing df and/or h produces a set of I–V curves among which the red dashed line

Unipolar magnetic field pulses as an advantageous tool for ultrafast operations in superconducting Josephson “atoms”

• Daria V. Popolitova,
• Nikolay V. Klenov,
• Igor I. Soloviev,
• Sergey V. Bakurskiy and
• Olga V. Tikhonova

Beilstein J. Nanotechnol. 2019, 10, 1548–1558, doi:10.3762/bjnano.10.152

• modern quantum physics is the transfer and storage of quantum information. This is why the development of quantum logic protocols using the fast state control of promising qubits and registers is of great importance. Superconducting artificial atoms based on Josephson junction circuits underlie a number

• [3]), where Josephson energies of the elements are EJos, EJos and αEJos (α = 0.9, junctions depicted as crosses). The characteristic Josephson energy EJos is 80 times larger than the characteristic Coulomb energy of the heterostructures. φ is the generalized coordinate associated with the Josephson

• junction phases. (b) A “Not”-operation in a double-well potential of the flux-driven superconducting meta-atom (α = 1.5) is shown as a transition between the states with certain values of the magnetic moment (these states correspond to the energy levels of E1 and E2, respectively). Applied adjusting

Periodic Co/Nb pseudo spin valve for cryogenic memory

• Nikolay Klenov,
• Yury Khaydukov,
• Sergey Bakurskiy,
• Roman Morari,
• Igor Soloviev,
• Vladimir Boian,
• Thomas Keller,
• Mikhail Kupriyanov,
• Anatoli Sidorenko and
• Bernhard Keimer

Beilstein J. Nanotechnol. 2019, 10, 833–839, doi:10.3762/bjnano.10.83

• us in the future to study the possible influence of superconductivity on the magnetic configuration via electromagnetic [38][39] or exchange [40][41] mechanisms. In conclusion, we have proposed a memory element based on a Josephson junction with a weak link composed of a periodic S/F structure that

A zero-dimensional topologically nontrivial state in a superconducting quantum dot

• Pasquale Marra,
• Alessandro Braggio and
• Roberta Citro

Beilstein J. Nanotechnol. 2018, 9, 1705–1714, doi:10.3762/bjnano.9.162

• simplest realization of such a 0D topological superconductor, i.e., a quantum dot [51][52][53][54] coupled with two superconducting leads in a magnetic Zeeman field, forming a superconductor–quantum dot–superconductor (SC–QD–SC) Josephson junction. Zero-energy modes and the corresponding CPR

• temperatures can reveal the presence of such discontinuities. Moreover, the presence of the topological transition can be probed indirectly by a measure of the critical current of the junction as a function of the Zeeman field or gate voltage. An SC–QD–SC Josephson junction realized by a two-level quantum dot

Robust topological phase in proximitized core–shell nanowires coupled to multiple superconductors

• Tudor D. Stanescu,
• Anna Sitek and
• Andrei Manolescu

Beilstein J. Nanotechnol. 2018, 9, 1512–1526, doi:10.3762/bjnano.9.142

• superconductors. A non-zero phase difference was shown to stabilize the topological phase in a Josephson junction across a 2D electron gas with Rashba spin-orbit coupling and in-plane magnetic field [42] and in a topological insulator nanoribbon coupled with two superconductors [43]. Here, for concreteness, we

Revealing the interference effect of Majorana fermions in a topological Josephson junction

• Jie Liu,
• Tiantian Yu and
• Juntao Song

Beilstein J. Nanotechnol. 2018, 9, 520–529, doi:10.3762/bjnano.9.50

• the local density of states (DOS) in a topological Josephson junction. We show that the well-known 4π Josephson effect originates from the interference effect between two Majorana fermions (MFs) that are localized at the Josephson junction. In addition, the DOS for electrons (holes) shows the 4π

• combined to form a topological Josephson junction (Top-JJ), the period of the supercurrent is 4π if MFs exist at the ends of both wires. This is different from the trivial case without MFs. In the trivial case in which only Cooper pairs can tunnel, the period is 2π. Since MFs have only half a degree of

• of the 4π Josephson current is not consistent with the theoretical prediction [35][36][37][38][39][40][41]. To distinguish the 4π information of MFs, it is necessary to reveal additional characteristic properties of such a Josephson junction. In this paper, we study a Top-JJ composed of two

Beyond Moore’s technologies: operation principles of a superconductor alternative

• Igor I. Soloviev,
• Nikolay V. Klenov,
• Sergey V. Bakurskiy,
• Mikhail Yu. Kupriyanov,
• Alexander L. Gudkov and
• Anatoli S. Sidorenko

Beilstein J. Nanotechnol. 2017, 8, 2689–2710, doi:10.3762/bjnano.8.269

• a deep analogy between superconducting logic cells and von Neuman cellular automata [16] where short-range interactions are predominant. The nonlinear element in superconducting circuits is the Josephson junction. It is a weak link between two superconductors, e.g., the most commonly used

• superconductor–isolator–superconductor (SIS) sandwich structure. One of the most important parameters of a Josephson junction is its critical current, Ic. This is the maximum superconducting current capable of flowing through the junction. A Josephson junction can be switched from the superconducting to the

• model with capacitance (RSJC) [18]. This model presents a Josephson junction as a parallel connection of the junction itself transmitting only the superconducting current, Is, and a resistor and a capacitor with the corresponding currents, Ir = V/R and Icap = C(∂V/∂t), where t is the time. The total