Roadmap on Nanoscale Superconductivity for Quantum Technologies

Abstract

In 2025, the Year of Quantum Science and Technology, we celebrate a century of quantum mechanics, witnessing a surge in activities that illuminate its inherent strangeness and drive technological innovation. Superconductivity, discovered 114 years ago, stands as a prime example, offering direct and compelling evidence of macroscopic quantum phenomena. Beyond its ability to conduct immense currents without loss, superconductivity reveals the quantum realm operating on a scale we can directly observe and manipulate. The macroscopic quantum coherence, where an ensemble of particles is described by a single wave function, leads to remarkable consequences: dissipation-less current and flux quantization - the basic properties exploited in superconducting quantum circuit fabrication. This Roadmap has been inspired by intensive discussions and collaborations emerging from the European COST Action CA21144 (SuperQuMap - Superconducting Nanodevices and Quantum Materials for Coherent Manipulation). The roadmap outlines the network's concrete activities, driving advancements in superconductor-based quantum technologies and charting future directions. Spanning fundamental research to practical applications, the roadmap incorporates insights from industry partners developing quantum computation. It begins by exploring quantum materials, highlighting how topology and electronic correlations could catalyze a quantum leap in technology. We then delve into manipulating the superconducting phase, leveraging advancements in magnetism, 3D fabrication, and tunable correlations. Further, we showcase the advanced microscopy techniques - such as angle-resolved photoemission spectroscopy and scanning probes - used to visualize quantum behavior. Finally, and crucially, we detail the quantum devices developed within the network, and their transformative impact on modern quantum computing approaches.

arXiv comment120 pages, 39 figures

References in corpus (120)

• 2D materials and van der Waals heterostructures
• Supplementary information for "Quantum supremacy using a programmable superconducting processor"
• Charge insensitive qubit design derived from the Cooper pair box
• New directions in the pursuit of Majorana fermions in solid state systems
• Coherent control of macroscopic quantum states in a single-Cooper-pair box
• A Quantum Engineer's Guide to Superconducting Qubits
• Fermi-liquid instabilities at magnetic quantum phase transitions
• Topological Materials: Weyl Semimetals
• Micrometer-scale ballistic transport in encapsulated graphene at room temperature
• Manipulating the Quantum State of an Electrical Circuit
• Evidence of Ising pairing in superconducting NbSe${}_2$ atomic layers
• Scanning tunneling spectroscopy of high-temperature superconductors
• High cooperativity in coupled microwave resonator ferrimagnetic insulator hybrids
• Fluxonium: single Cooper pair circuit free of charge offsets
• A spin triplet supercurrent through the half-metallic ferromagnet CrO2
• The hot pick-up technique for batch assembly of van der Waals heterostructures
• Quantum error correction below the surface code threshold
• Divergent nematic susceptibility in an iron arsenide superconductor
• Demonstrating sub-3 ps temporal resolution in a superconducting nanowire single-photon detector
• Electronic structure of quantum materials studied by angle-resolved photoemission spectroscopy
• The Physics of Pair Density Waves
• Scanning nano-SQUID with single electron spin sensitivity
• A Semiconductor Nanowire-Based Superconducting Qubit
• Topological superconductivity in a van der Waals heterostructure
• Superfluidity and Quantum Geometry in Twisted Multilayer Systems
• Ironing out the details of unconventional superconductivity
• Topological phases with parafermions: theory and blueprints
• Discovery of two-dimensional anisotropic superconductivity at KTaO${}_3$ (111) interfaces
• Angle-resolved photoemission spectroscopy and its application to topological materials
• Two-dimensional superconductivity at the surfaces of KTaO3 gated with ionic liquid
• Magnetic Vortex Resonance in Patterned Ferromagnetic Dots
• Nano Superconducting Quantum Interference device: a powerful tool for nanoscale investigations
• Extreme magnetic field-boosted superconductivity
• Laser-annealing Josephson junctions for yielding scaled-up superconducting quantum processors
• Chiral d-wave superconductivity in doped graphene
• Single magnetic adsorbates on s-wave superconductors
• Decoherence in Josephson-junction qubits due to critical current fluctuations
• Giant thermal Hall conductivity from neutral excitations in the pseudogap phase of cuprates
• Self-aligned nanoscale SQUID on a tip
• New Constraints on Dark Photon Dark Matter with Superconducting Nanowire Detectors in an Optical Haloscope
• Quantum breakdown of superconductivity in low-dimensional materials
• Impact of Size Effect on Graphene Nanoribbon Transport
• The Quantum Twisting Microscope
• High-Fidelity, Frequency-Flexible Two-Qubit Fluxonium Gates with a Transmon Coupler
• Fast readout and reset of a superconducting qubit coupled to a resonator with an intrinsic Purcell filter
• Flat bands, strange metals, and the Kondo effect
• Bogoliubov Fermi surfaces: General theory, magnetic order, and topology
• Imaging superconducting vortex core and lattice with the scanning tunneling microscope
• Magnon-Fluxon interaction in a ferromagnet/superconductor heterostructure
• Incoherent transport across the strange metal regime of highly overdoped cuprates
• Spectroscopy of bulk and few-layer superconducting NbSe${}_2$ with van der Waals tunnel junctions
• A superconducting-nanowire single-photon camera with 400,000 pixels
• Single-photon detection using high-temperature superconductors
• Direct Observation of a Uniaxial Stress-driven Lifshitz Transition in Sr${}_2$RuO${}_4$
• Ising superconductivity and magnetism in NbSe${}_2$
• Resonance from antiferromagnetic spin fluctuations for superconductivity in UTe${}_2$
• Smectic Pair Density Wave Order in EuRbFe4As4
• Spin-charge interconversion in KTaO${}_3$ two-dimensional electron gases
• Gate-Tunable Graphene Hall Sensors with High Magnetic Field Sensitivity
• Superconductivity with broken time reversal symmetry in ion irradiated Ba${}_{0.27}$K${}_{0.73}$Fe${}_2$As${}_2$ single crystals
• Fabrication and Transport Properties of 100 m Class Sr0.6K0.4Fe2As2 Wires and Pancake Coils
• SQUID-on-tip with single-electron spin sensitivity for high-field and ultra-low temperature nanomagnetic imaging
• On the origin of the controversial electrostatic field effect in superconductors
• Sign reversal of the AC and DC supercurrent diode effect and 0-$\pi$-like transitions in ballistic Josephson junctions
• Superconductivity in an extreme strange metal
• Direct evidence for Cooper pairing without a spectral gap in a disordered superconductor above $T_C$
• Topological Ultranodal pair states in iron-based superconductors
• Superconducting Arcs
• Operando imaging of all-electric spin texture manipulation in ferroelectric and multiferroic Rashba semiconductors
• NanoSQUIDs: Basics & recent advances
• Misfit layer compounds: a platform for heavily-doped two-dimensional transition metal dichalcogenides
• Magnetic, thermal, and topographic imaging with a nanometer-scale SQUID-on-cantilever scanning probe
• Twisted cuprate van der Waals heterostructures with controlled Josephson coupling
• Superconducting THz sources with 12% power efficiency
• Realization of High-Fidelity CZ Gate based on a Double-Transmon Coupler
• Colossal orbital-Edelstein effect in non-centrosymmetric superconductors
• Proximity superconductivity in atom-by-atom crafted quantum dots
• Spin-wave eigenmodes in direct-write 3D nanovolcanoes
• Giant transition-state enhancement of quasiparticle spin-Hall effect in an exchange-spin-split superconductor detected by non-local magnon spin-transport
• Revealing the single electron pocket of FeSe in a single orthorhombic domain
• Temperature-dependent spin-transport and current-induced torques in superconductor/ferromagnet heterostructures
• Misfit Layered Compounds: Unique, Tunable Heterostructured Materials with Untapped Properties
• Grooved Dayem nanobridges as building blocks of high-performance YBa${}_2$Cu${}_3$O${}_{7-\delta }$ SQUID magnetometers
• Tunable pure spin supercurrents and the demonstration of a superconducting spin-wave device
• Phase diagram of Eu magnetic ordering in Sn-flux-grown Eu(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$ single crystals
• Mechanism of generation of a Josephson phase shift by an Abrikosov vortex
• High-T${}_c$ cuprates: a story of two electron subsystems
• Vortex jets generated by edge defects in current-carrying superconductor thin strips
• Modular Superconducting Qubit Architecture with a Multi-chip Tunable Coupler
• Ultradense Tailored Vortex Pinning Arrays in Superconducting YBa${}_2$Cu${}_3$O${}_{7-\delta }$ Thin Films Created by Focused He Ion Beam Irradiation for Fluxonics Applications
• Alternating Bias Assisted Annealing of Amorphous Oxide Tunnel Junctions
• Quantum-well states at the surface of the heavy-fermion superconductor URu${}_2$Si${}_2$
• A micro-SQUID with dispersive readout for magnetic scanning microscopy
• Dynamics of two ferromagnetic insulators coupled by superconducting spin current
• Generation of spin-triplet Cooper pairs via a canted antiferromagnet
• Protection of Ising spin-orbit coupling in bulk misfit superconductors
• Magnon-Cooparons in magnet-superconductor hybrids
• Engineered magnetization and exchange stiffness in direct-write Co-Fe nanoelements
• Experimental observation of an anomalous peak in isofield M(T) curves in BaFe${}_2$(As${}_{1-x}$P${}_x$)${}_2$ resembling the fish-tail in $M$($H$) curves further suggesting a possible phase transition in the irreversible regime
• Vortex matching at 6 T in YBa${}_2$Cu${}_3$O${}_{7-\delta }$ thin films by imprinting a 20 nm-periodic pinning array with a focused helium ion beam
• Mesoscopic superconducting memory based on bistable magnetic textures
• 2D high temperature superconductor integration in contact printed circuit boards
• magnetoARPES: Angle Resolved Photoemission Spectroscopy with Magnetic Field Control
• Noise properties of nanoscale YBCO Josephson junctions
• Josephson vortex-based memory
• A high-temperature superconducting weak-link defined by ferroelectric field-effect
• Boosting the STM's spatial and energy resolution with double-functionalized probe tips
• Artificial heavy fermions in a van der Waals heterostructure
• Scanning quantum vortex microscopy reveals thickness-dependent pinning nano-network in superconducting Nb-films
• Nature of the current-induced insulator-to-metal transition in Ca${}_2$RuO${}_4$ as revealed by transport-ARPES
• Terahertz emission from mutually synchronized standalone Bi2Sr2CaCu2O8+x intrinsic-Josephson-junction stacks
• Multi-Atom Quasiparticle Scattering Interference for Superconductor Energy-Gap Symmetry Determination
• How to Build a Quantum Supercomputer: Scaling from Hundreds to Millions of Qubits
• Advanced SQUID-on-lever scanning probe for high-sensitivity magnetic microscopy with sub-100-nm spatial resolution
• Neel proximity effect in superconductor/antiferromagnet heterostructures
• Shaping graphene superconductivity with nanometer precision
• The feedback driven atomic scale Josephson microscope
• Performance-centric roadmap for building a superconducting quantum computer
• Revealing Josephson vortex dynamics in proximity junctions below critical current
• A hybrid ferromagnetic transmon qubit: circuit design, feasibility and detection protocols for magnetic fluctuations

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