Signatures of Enhanced Superconducting Properties in Niobium Cavities

• URL: http://arxiv.org/abs/2103.10601v3
• Date: Wed, 15 Jan 2025 04:12:59 GMT
• Title: Signatures of Enhanced Superconducting Properties in Niobium Cavities
• Authors: D. Bafia, A. Grassellino, M. Checchin, J. F. Zasadzinski, A. Romanenko,
• Abstract summary: We report an anomalous frequency dip in Nb cavities, indicative of enhanced superconducting properties at $T ll T_c$.<n>We also present the first demonstration of the coherence peak in the AC conductivity of Nb SRF cavities.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: Superconducting radio-frequency (SRF) niobium cavities are critical for modern particle accelerators, as well as for advancing superconducting quantum systems and enabling ultra-sensitive searches for new physics. In this work, we report a systematic observation of an anomalous frequency dip in Nb cavities, which occurs at temperatures just below the critical temperature ($T_\mathrm{c}$), indicative of enhanced superconducting properties at $T \ll T_c$. The magnitude of this dip is strongly correlated with the RF surface resistance, impurity distribution near the surface, and $T_\mathrm{c}$. We also present the first demonstration of the coherence peak in the AC conductivity of Nb SRF cavities. By comparing recent theories developed to model this experimental data, we show that the frequency dip feature, larger coherence peak height, and reduction in the temperature-dependent surface resistance with RF current occur at minimal but finite levels of disorder.

Related papers

• Electron-Electron Interactions in Device Simulation via Non-equilibrium Green's Functions and the GW Approximation [71.63026504030766]
  electron-electron (e-e) interactions must be explicitly incorporated in quantum transport simulation. This study is the first one reporting large-scale atomistic quantum transport simulations of nano-devices under non-equilibrium conditions.
  arXiv  Detail & Related papers  (2024-12-17T15:05:33Z)
• Measuring kinetic inductance and superfluid stiffness of two-dimensional superconductors using high-quality transmission-line resonators [1.9343861862849647]
  We demonstrate a new technique that employs high-quality-factor superconducting resonators to measure the kinetic inductance. We analyze the equivalent circuit model to extract the kinetic inductance, super stiffness, penetration depth, and ratio of imaginary and real parts of the complex conductivity. Our method will be useful for practitioners in the growing fields of superconducting physics, materials science, and quantum sensing.
  arXiv  Detail & Related papers  (2024-07-13T15:26:00Z)
• Superfluid stiffness of twisted multilayer graphene superconductors [1.374933941124824]
  We report the measurement of $rho_s$ in magic-angle twisted trilayer graphene (TTG) We find a linear temperature dependence of $rho_s$ at low temperatures and nonlinear Meissner effects in the current bias dependence. Our results provide strong evidence for nodal superconductivity in TTG and put strong constraints on the mechanisms of these graphene-based superconductors.
  arXiv  Detail & Related papers  (2024-06-19T18:00:04Z)
• Minimizing Kinetic Inductance in Tantalum-Based Superconducting Coplanar Waveguide Resonators for Alleviating Frequency Fluctuation Issues [4.3869590932623606]
  tantalum films exhibit significantly larger kinetic inductances than aluminum or niobium. We achieve a reduction in resonator frequency fluctuation by a factor of more than 100. Our findings open up new avenues for the enhanced utilization of tantalum in large-scale superconducting chips.
  arXiv  Detail & Related papers  (2024-05-05T14:49:33Z)
• Revealing Symmetry-Broken Superconducting Configurations by Density Functional Theory [0.0]
  A coherent theory for the superconductivity of both conventional and unconventional superconductors is currently lacking. Here we show that superconductivity arises from the formation of a symmetry-broken superconducting configuration due to atomic perturbation of the normal conducting configuration. The present work highlights that in conventional superconductors, SODTs are embedded within the bulk materials and are easily destroyed by phonon vibrations. In unconventional superconductors such as YBa2Cu3O7 (YBCO7), SODTs are protected by a layered pontoon structure with very weak bonding to the bulk materials.
  arXiv  Detail & Related papers  (2024-03-31T15:27:12Z)
• Superconductivity in a Topological Lattice Model with Strong Repulsion [1.1305119700024195]
  We introduce a minimal 2D lattice model that incorporates time-reversal symmetry, band topology, and strong repulsive interactions. We demonstrate that it is formed from the weak pairing of holes atop the QSH insulator. Motivated by this, we elucidate structural similarities and differences between our model and those of TBG in its chiral limit.
  arXiv  Detail & Related papers  (2023-08-21T18:00:01Z)
• Characterizing Niobium Nitride Superconducting Microwave Coplanar Waveguide Resonator Array for Circuit Quantum Electrodynamics in Extreme Conditions [1.2627743222524832]
  Niobium nitride (NbN) is a promising material for applications in superconducting quantum technology. NbN-based devices and circuits are sensitive to decoherence sources such as two-level system (TLS) defects. We numerically and experimentally investigate NbN superconducting microwave coplanar waveguide resonator arrays.
  arXiv  Detail & Related papers  (2023-06-04T13:24:51Z)
• High quality superconducting Nb co-planar resonators on sapphire substrate [0.7259990655101205]
  In the high temperature regime, we demonstrate that the Nb film residual surface resistance is comparable to that observed in the ultra-high quality, bulk Nb 3D superconducting radio frequency cavities. At low temperature both the resonator quality factor and frequency can be well explained using the two-level system models.
  arXiv  Detail & Related papers  (2022-07-26T16:35:51Z)
• First design of a superconducting qubit for the QUB-IT experiment [50.591267188664666]
  The goal of the QUB-IT project is to realize an itinerant single-photon counter exploiting Quantum Non Demolition (QND) measurements and entangled qubits. We present the design and simulation of the first superconducting device consisting of a transmon qubit coupled to a resonator using Qiskit-Metal.
  arXiv  Detail & Related papers  (2022-07-18T07:05:10Z)
• Stabilizing and improving qubit coherence by engineering noise spectrum of two-level systems [52.77024349608834]
  Superconducting circuits are a leading platform for quantum computing. Charge fluctuators inside amorphous oxide layers contribute to both low-frequency $1/f$ charge noise and high-frequency dielectric loss. We propose to mitigate those harmful effects by engineering the relevant TLS noise spectral densities.
  arXiv  Detail & Related papers  (2022-06-21T18:37:38Z)
• Thermal self-oscillations in monolayer graphene coupled to a superconducting microwave cavity [58.720142291102135]
  We observe thermal self-oscillations in a monolayer graphene flake coupled to superconducting resonator. The experimental observations fit well with theoretical model based on thermal instability. The modelling of the oscillation sidebands provides a method to evaluate electron phonon coupling in disordered graphene sample at low energies.
  arXiv  Detail & Related papers  (2022-05-27T15:38:41Z)
• Recent Developments in Quantum-Circuit Refrigeration [0.0]
  In 2017, the invention of a quantum-circuit refrigerator inspired a series of experimental studies. Theoretically, it is predicted that state-of-the-art superconducting resonators and qubits can be reset with an infidelity lower than $10-4$ in nanoseconds. In the future, the QCR may be experimentally used to quickly reset superconducting qubits, and hence assist in the great challenge of building a practical quantum computer.
  arXiv  Detail & Related papers  (2021-11-22T14:27:26Z)
• Engineering the Radiative Dynamics of Thermalized Excitons with Metal Interfaces [58.720142291102135]
  We analyze the emission properties of excitons in TMDCs near planar metal interfaces. We find suppression or enhancement of emission relative to the point dipole case by several orders of magnitude. nanoscale optical cavities are a viable pathway to generating long-lifetime exciton states in TMDCs.
  arXiv  Detail & Related papers  (2021-10-11T19:40:24Z)
• TOF-SIMS Analysis of Decoherence Sources in Nb Superconducting Resonators [48.7576911714538]
  Superconducting qubits have emerged as a potentially foundational platform technology. Material quality and interfacial structures continue to curb device performance. Two-level system defects in the thin film and adjacent regions introduce noise and dissipate electromagnetic energy.
  arXiv  Detail & Related papers  (2021-08-30T22:22:47Z)
• Measurement of the Low-temperature Loss Tangent of High-resistivity Silicon with a High Q-factor Superconducting Resonator [58.720142291102135]
  We present the direct loss tangent measurement of a high-resist intrinsicivity (100) silicon wafer in the temperature range from 70 mK to 1 K. The measurement was performed using a technique that takes advantage of a high quality factor superconducting niobium resonator.
  arXiv  Detail & Related papers  (2021-08-19T20:13:07Z)
• Frequency fluctuations of ferromagnetic resonances at milliKelvin temperatures [50.591267188664666]
  Noise is detrimental to device performance, especially for quantum coherent circuits. Recent efforts have demonstrated routes to utilizing magnon systems for quantum technologies, which are based on single magnons to superconducting qubits. Researching the temporal behavior can help to identify the underlying noise sources.
  arXiv  Detail & Related papers  (2021-07-14T08:00:37Z)
• Cavity-immune features in the spectra of superradiant crossover laser pulses [0.0]
  Lasing in the bad cavity regime has promising applications in precision metrology due to the reduced sensitivity to cavity noise. We find that by detuning the cavity resonance, the influence of the cavity noise on the peak lasing frequency can be eliminated to first order. Experimental results are compared to a model based on a Tavis-Cummings Hamiltonian, which enables us to investigate the interplay between different thermal velocity classes.
  arXiv  Detail & Related papers  (2021-04-27T16:30:04Z)
• Mechanical Decoupling of Quantum Emitters in Hexagonal Boron Nitride from Low-Energy Phonon Modes [52.77024349608834]
  Quantum emitters in hexagonal Boron Nitride (hBN) were recently reported to hol a homogeneous linewidth according to the Fourier-Transform limit up to room temperature. This unusual observation was traced back to decoupling from in-plane phonon modes which can arise if the emitter is located between two planes of the hBN host material.
  arXiv  Detail & Related papers  (2020-04-22T20:00:49Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.