A superconducting LC resonator in a multi-tesla magnetic field for tabletop kHz gravitational-wave detection
Year: 2026
Type: preprint
Abstract: We present a concept for a superconducting inductance--capacitance (LC) resonator immersed in a magnetic field for gravitational-wave detection in the kHz band. In the long-wavelength limit, a gravitational wave in a static magnetic field induces an oscillating magnetic-field perturbation proportional to the static magnetic field applied to the resonator and to the gravitational-wave strain. We show that a superconducting pickup circuit can convert this perturbation into a flux signal read out by a superconducting quantum interference device (SQUID)-based or quantum-limited amplifier chain. Inspired by resonant-mass detectors, we develop a three-loop coupled-circuit model and derive the equivalent strain-noise spectrum, including thermal noise, SQUID backaction, and measurement imprecision. Prototype measurements demonstrate a quality factor of $Q\simeq 5\times 10^5$, while $Q=10^7$ is considered as a future development target. Under the assumed flux coupling and an idealized quantum-limited SQUID noise model, optimized circuits yield projected strain sensitivities of order $10^{-21}\,\mathrm{Hz}^{-1/2}$ over $100\,\mathrm{Hz}$ bands in the $1$--$20\,\mathrm{kHz}$ range. Increasing the active high-field volume and improving quantum-limited readout could enable further sensitivity gains. This compact, tunable detector concept could complement interferometric gravitational-wave searches and motivate investigations of high-frequency astrophysical sources.
Source: arXiv (Cornell University)
Institutions: Istituto Nazionale di Fisica Nucleare, Sezione di Padova, University of Padua, Istituto Nazionale di Fisica Nucleare, Gruppo Collegato di Salerno, Fondazione Bruno Kessler, Istituto Nazionale di Fisica Nucleare, Trento Institute for Fundamental Physics And Applications, Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, Istituto Nazionale di Fisica Nucleare, Sezione di Torino, University of Turin
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7223312227