Magnetic Field Tolerant Superconducting Spiral Resonators for Circuit QED (2406.10386v1)
Abstract: We present spiral resonators of thin film niobium (Nb) that exhibit large geometric inductance, high critical magnetic fields and high single photon quality factors. These low loss geometric inductors can be a compelling alternative to kinetic inductors to create high-impedance superconducting devices for applications that require magnetic fields. By varying the spiral pitch, we realize resonators with characteristic impedances ranging from 3.25-7.09 k{\Omega}. We measure the temperature and magnetic field dependent losses and find that the high-impedance resonators maintain an intrinsic quality factor above {\sim} 105 for parallel magnetic fields of up to 1 T. These properties make spiral Nb resonators a promising candidate for quantum devices that require circuit elements with high impedance and magnetic field resilience.