MgB$_2$ Thermal Kinetic Inductance Detector

TL;DR

This paper demonstrates MgB$_2$-based Thermal Kinetic Inductance Detectors operating from below 1 K to 20 K, showing phonon noise-limited performance and detailed characterization of their electrical, thermal, and noise properties.

Contribution

It introduces MgB$_2$ as a material for TKIDs and provides comprehensive performance characterization across a wide temperature range.

Findings

Operates effectively from below 1 K to 20 K

Achieves phonon noise-limited performance between 4 and 8 K

Provides detailed electrical, thermal, and noise characterization

Abstract

Thermal Kinetic Inductance Detectors (TKIDs) inherently combine the phonon-limited noise performance of traditional bolometers with the array scalability and responsivity of superconducting kinetic inductance detectors. Using a superconducting resonator as the thermally sensitive element provides high responsivity and tunable dynamic range, with phonon noise set by the cryogenic operating temperature of the free-standing membrane. In this work, MgB$_2$-based TKIDs are demonstrated operating from below 1 K up to 20 K with characterized noise-equivalent power (NEP) using integrated on-membrane heaters. A comprehensive characterization of electrical, thermal, and noise properties is presented. Phonon noise-limited performance is demonstrated from 4 to 8 K.