Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:1609.08525 · Scientific Reports

Phase-driven charge manipulation in Hybrid Single-Electron Transistor

Emanuele Enrico, Elia Strambini, Francesco Giazotto

Published Oct 12, 2017• 7 citations
arXivHTMLPDF

Abstract

Phase-tunable hybrid devices, built upon nanostructures combining normal metal and superconductors, have been the subject of intense studies due to their numerous combinations of different charge and heat transport configurations. They exhibit solid applications in quantum metrology and coherent caloritronics. Here we propose and realize a new kind of hybrid device with potential application in single charge manipulation and quantized current generation. We show that by tuning superconductivity on two proximized nanowires, coupled via a Coulombic normal-metal island, we are able to control its charge state configuration. This device supports a one-control-parameter cycle being actuated by the sole magnetic flux. In a voltage biased regime, the phase-tunable superconducting gaps can act as energy barriers for charge quanta leading to an additional degree of freedom in single electronics. The resulting configuration is fully electrostatic and the current across the device is governed by the quasiparticle populations in the source and drain leads. Notably, the proposed device can be realized using standard nanotechniques opening the possibility to a straightforward coupling with the nowadays well developed superconducting electronics.

DOI
10.1038/s41598-017-13894-z

Related papers

Quantum Interference Hybrid Single-Electron Transistor

Emanuele Enrico, Elia Strambini, Francesco Giazotto

The manipulation of single charge quanta in solid state systems has been a field of active interest for several decades. At the basis of such structures lays the Coulombic repulsion between electrons in a small metallic island yielding the so-called Coulomb-blockade regime. Many quantum phenomena, such as the tunnelling effect or the Josephson coupling in superconducting junctions, have been exploited so far to control the charging state of a conducting island, and enable a number of applications ranging from on-chip cooling and current generation to single-photon detection. Yet, in all Coulombic systems the external control parameters play a crucial role, reaching sometimes a rather complex experimental configuration. Here we show that quantum interference established in a superconducting nanowire can provide a phase-tunable energy barrier which allows charge manipulation with enhanced functionalities. This additional degree of freedom for single electronics stems from the coupling between magnetic flux-dependent proximity effect and charging levels discretization present in a Coulomb-blockaded island. Our quantum interference nanostructure represents the first realization of a superconducting hybrid single-electron transistor called SQUISET in which the charging landscape is phase-coherently manipulated by an external magnetic flux. The interferometric nature of the transistor adds new perspectives to single electronics making it a promising alternative building block in quantum metrology, coherent caloritronics, and quantum information technology.

•Sep 27, 2016•0 citations

Gate tunable coherent heat transport : Study of the heat transfer in gate controlled hybrid superconducting systems

Sebastiano BATTISTI

In recent decades, the scientific results of superconducting electronics have been remarkable. Observation of complex quantum phenomena, such as quantum coherence or manipulation of electronic quantum states, is nowadays commonplace. The thermal counterpart of superconductive electronics is the field of coherent caloritronics, which is used to control and manage heat transfer in superconducting circuits. Micro- and nano-structured superconductors are excellent laboratories for investigating and implementing low-temperature thermal manipulation architectures, primarily due to their unique density-of-states and coherence properties. Although this topic has been extensively studied in recent decades and several experimental and theoretical results have been achieved, flexible, scalable architectures for thermal transport management systems and reliable platforms for thermal energy manipulation remain missing. The lack of practical implementation of coherent caloritronic devices is primarily due to the need to utilize magnetic fields in all proposed architectures. This makes the devices less scalable and more complex, as is usually the case with magnetic fields.The purpose of our work is to pave the way for a real and scalable implementation of caloritronic architectures that leverage electrical fields. In fact, given the experience with CMOS transistors, it is evident that electrical fields are easier to generate and more scalable than magnetic fields, which require uncomfortable coils or flux lines. The fundamental structure used throughout this thesis is the top-gate architecture, consisting of a metallic electrode separated from the portion of the device where we want to apply the electric field by an insulating layer.This thesis consists of two main results: the first one refers to the generation of thermoelectricity with superconductors and its manipulation with the application of a gate potential; the second one refers to the photonic heat transfer due to electron-photon coupling in superconducting circuits, which we will show can be manipulated via a top gate. Both of these results had already been achieved using magnetic fields, rendering the proposed devices practically useless for real applications. We will show that to reach our results, we had to find new solutions and implement novel ideas to make the structures suitable for gate tuning.

•Jun 30, 2026•0 citations

Interplay of Andreev Reflection and Coulomb Blockade in Hybrid Superconducting Single-Electron Transistors

Laura Sobral Rey, David Christian Ohnmacht, Clemens B. Winkelmann +3 more

We study the interplay between Coulomb blockade and superconductivity in a tunable superconductor-superconductor-normal-metal single-electron transistor. The device is realized by connecting the superconducting island via an oxide barrier to the normal-metal lead and with a break junction to the superconducting lead. The latter enables Cooper pair transport and (multiple) Andreev reflection. We show that these processes are relevant also far above the superconducting gap and that signatures of Coulomb blockade may reoccur at high bias while they are absent for small bias in the strong-coupling regime. Our experimental findings agree with simulations using a rate equation approach in combination with the full counting statistics of multiple Andreev reflection.

arXiv:2306.05758•Physical Review Letters•Feb 2, 2024•5 citations

Single charge transport in a fully superconducting SQUISET locally tuned by self-inductance effects

Emanuele Enrico, Luca Croin, Elia Strambini +1 more

We present a single-electron device for the manipulation of charge states via quantum interference in nanostructured electrodes. Via self-inductance effects, we induce two independent magnetic fluxes in the electrodes and we demonstrate sensitivity to single charge states and magnetic field at variable temperature. Moreover, our approach allows us to demonstrate local and independent control of the single-particle conductance between nano-engineered tunnel junctions in a fully superconducting quantum interference single-electron transistor, thereby increasing the flexibility of our single-electron transistors. Our devices show a robust modulation of the current-to-flux transfer function via control currents while exploiting the single-electron filling of a mesoscopic superconducting island. Further applications of the device concept to single charge manipulation and magnetic-flux sensing are also discussed.

arXiv:1901.01248•AIP Advances•May 1, 2022•1 citation

Hybrid single-electron turnstile - Towards a quantum standard of electric current

Jukka P Pekola, D. V. Averin, Sergey G. Kafanov +9 more

First I discuss various candidates of single-electron current pumps for quantum metrology. Then I focus on the hybrid normal-metal-superconductor turnstile in the form of a one-island single-electron transistor with one gate. The device demonstrates robust current plateaus at multiple levels of ef at frequency f. I discuss the various error mechanisms, based on our experiments and theoretical considerations. Ultimately the quantization accuracy is expected to be limited by either two-electron tunneling or by Cooper-pair-electron co-tunneling. We predict that it should be possible to achieve the metrological accuracy of 10-8, while maintaining the quantized current on the level of more than 10 pA, just by one turnstile with realistic parameters using aluminium as a superconductor. Recently we have managed to run ten turnstiles in parallel increasing the current level to above 100 pA. Work on suppressing the harmful sub-gap leakage current is in progress with encouraging experimental results.

•Jun 1, 2010•1 citation

Hybrid Josephson Rhombus: A Superconducting Element with Tailored Current-Phase Relation

Luca Banszerus, C. W. Andersson, W. Marshall +4 more

Controlling the current-phase relation (CPR) of Josephson elements is essential for tailoring the eigenstates of superconducting qubits, tuning the properties of parametric amplifiers, and designing nonreciprocal superconducting devices. Here, we introduce the hybrid Josephson rhombus, a highly tunable superconducting circuit containing four semiconductor-superconductor hybrid Josephson junctions embedded in a loop. Combining magnetic frustration with gate-voltage-controlled tuning of individual Josephson couplings provides deterministic control of the harmonic content of the rhombus CPR. We show that, for balanced Josephson couplings at full frustration, the hybrid rhombus displays a π -periodic cos ( 2 φ ) potential, indicating coherent charge- 4 e transport. Tuning away from the balanced configuration, we observe a superconducting diode effect with efficiency exceeding 25%. These results showcase the potential of hybrid Josephson rhombi as fundamental building blocks for noise-resilient qubits and quantum devices with custom transport properties.

arXiv:2406.20082•Physical Review X•Feb 4, 2025•14 citations
Phase-tunable hybrid devices, built upon nanostructures combining normal metal and superconductors, have been the subject of intense studies due to their numerous combinations of different charge and heat transport configurations. They exhibit solid applications in quantum metrology and coherent caloritronics. Here we propose and realize a new kind of hybrid device with potential application in single charge manipulation and quantized current generation. We show that by tuning superconductivity on two proximized nanowires, coupled via a Coulombic normal-metal island, we are able to control its charge state configuration. This device supports a one-control-parameter cycle being actuated by the sole magnetic flux. In a voltage biased regime, the phase-tunable superconducting gaps can act as energy barriers for charge quanta leading to an additional degree of freedom in single electronics. The resulting configuration is fully electrostatic and the current across the device is governed by the quasiparticle populations in the source and drain leads. Notably, the proposed device can be realized using standard nanotechniques opening the possibility to a straightforward coupling with the nowadays well developed superconducting electronics.
The manipulation of single charge quanta in solid state systems has been a field of active interest for several decades. At the basis of such structures lays the Coulombic repulsion between electrons in a small metallic island yielding the so-called Coulomb-blockade regime. Many quantum phenomena, such as the tunnelling effect or the Josephson coupling in superconducting junctions, have been exploited so far to control the charging state of a conducting island, and enable a number of applications ranging from on-chip cooling and current generation to single-photon detection. Yet, in all Coulombic systems the external control parameters play a crucial role, reaching sometimes a rather complex experimental configuration. Here we show that quantum interference established in a superconducting nanowire can provide a phase-tunable energy barrier which allows charge manipulation with enhanced functionalities. This additional degree of freedom for single electronics stems from the coupling between magnetic flux-dependent proximity effect and charging levels discretization present in a Coulomb-blockaded island. Our quantum interference nanostructure represents the first realization of a superconducting hybrid single-electron transistor called SQUISET in which the charging landscape is phase-coherently manipulated by an external magnetic flux. The interferometric nature of the transistor adds new perspectives to single electronics making it a promising alternative building block in quantum metrology, coherent caloritronics, and quantum information technology.
In recent decades, the scientific results of superconducting electronics have been remarkable. Observation of complex quantum phenomena, such as quantum coherence or manipulation of electronic quantum states, is nowadays commonplace. The thermal counterpart of superconductive electronics is the field of coherent caloritronics, which is used to control and manage heat transfer in superconducting circuits. Micro- and nano-structured superconductors are excellent laboratories for investigating and implementing low-temperature thermal manipulation architectures, primarily due to their unique density-of-states and coherence properties. Although this topic has been extensively studied in recent decades and several experimental and theoretical results have been achieved, flexible, scalable architectures for thermal transport management systems and reliable platforms for thermal energy manipulation remain missing. The lack of practical implementation of coherent caloritronic devices is primarily due to the need to utilize magnetic fields in all proposed architectures. This makes the devices less scalable and more complex, as is usually the case with magnetic fields.The purpose of our work is to pave the way for a real and scalable implementation of caloritronic architectures that leverage electrical fields. In fact, given the experience with CMOS transistors, it is evident that electrical fields are easier to generate and more scalable than magnetic fields, which require uncomfortable coils or flux lines. The fundamental structure used throughout this thesis is the top-gate architecture, consisting of a metallic electrode separated from the portion of the device where we want to apply the electric field by an insulating layer.This thesis consists of two main results: the first one refers to the generation of thermoelectricity with superconductors and its manipulation with the application of a gate potential; the second one refers to the photonic heat transfer due to electron-photon coupling in superconducting circuits, which we will show can be manipulated via a top gate. Both of these results had already been achieved using magnetic fields, rendering the proposed devices practically useless for real applications. We will show that to reach our results, we had to find new solutions and implement novel ideas to make the structures suitable for gate tuning.
We study the interplay between Coulomb blockade and superconductivity in a tunable superconductor-superconductor-normal-metal single-electron transistor. The device is realized by connecting the superconducting island via an oxide barrier to the normal-metal lead and with a break junction to the superconducting lead. The latter enables Cooper pair transport and (multiple) Andreev reflection. We show that these processes are relevant also far above the superconducting gap and that signatures of Coulomb blockade may reoccur at high bias while they are absent for small bias in the strong-coupling regime. Our experimental findings agree with simulations using a rate equation approach in combination with the full counting statistics of multiple Andreev reflection.
We present a single-electron device for the manipulation of charge states via quantum interference in nanostructured electrodes. Via self-inductance effects, we induce two independent magnetic fluxes in the electrodes and we demonstrate sensitivity to single charge states and magnetic field at variable temperature. Moreover, our approach allows us to demonstrate local and independent control of the single-particle conductance between nano-engineered tunnel junctions in a fully superconducting quantum interference single-electron transistor, thereby increasing the flexibility of our single-electron transistors. Our devices show a robust modulation of the current-to-flux transfer function via control currents while exploiting the single-electron filling of a mesoscopic superconducting island. Further applications of the device concept to single charge manipulation and magnetic-flux sensing are also discussed.
First I discuss various candidates of single-electron current pumps for quantum metrology. Then I focus on the hybrid normal-metal-superconductor turnstile in the form of a one-island single-electron transistor with one gate. The device demonstrates robust current plateaus at multiple levels of ef at frequency f. I discuss the various error mechanisms, based on our experiments and theoretical considerations. Ultimately the quantization accuracy is expected to be limited by either two-electron tunneling or by Cooper-pair-electron co-tunneling. We predict that it should be possible to achieve the metrological accuracy of 10-8, while maintaining the quantized current on the level of more than 10 pA, just by one turnstile with realistic parameters using aluminium as a superconductor. Recently we have managed to run ten turnstiles in parallel increasing the current level to above 100 pA. Work on suppressing the harmful sub-gap leakage current is in progress with encouraging experimental results.
Controlling the current-phase relation (CPR) of Josephson elements is essential for tailoring the eigenstates of superconducting qubits, tuning the properties of parametric amplifiers, and designing nonreciprocal superconducting devices. Here, we introduce the hybrid Josephson rhombus, a highly tunable superconducting circuit containing four semiconductor-superconductor hybrid Josephson junctions embedded in a loop. Combining magnetic frustration with gate-voltage-controlled tuning of individual Josephson couplings provides deterministic control of the harmonic content of the rhombus CPR. We show that, for balanced Josephson couplings at full frustration, the hybrid rhombus displays a π -periodic cos ( 2 φ ) potential, indicating coherent charge- 4 e transport. Tuning away from the balanced configuration, we observe a superconducting diode effect with efficiency exceeding 25%. These results showcase the potential of hybrid Josephson rhombi as fundamental building blocks for noise-resilient qubits and quantum devices with custom transport properties.