International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz)

Demonstration of an NEP of 3.8×10−19 W/Hz1/2 at 1.54 THz in multiplexible superconducting microresonator detectors

Pieter de Visser, J. J. A. Baselmans, Juan Bueno, T. M. Klapwijk

Published Sep 1, 2014• 0 citations

Abstract

Microwave kinetic inductance detectors (MKIDs) promise high sensitivity, combined with device simplicity and intrinsic multiplexibility. We have measured the response and noise equivalent power (NEP) of an all-aluminium, antenna coupled MKID at 1.54 THz, both as a function of radiation power and as a function of readout power. Eight optical filters and a box-in-box configuration at the bath temperature, allow a large range of optical powers by varying the temperature of a black body source. In the range of 80 aW-700 fW the detector is photon-noise limited, with an optical efficiency of 48±8% for one polarisation, which is limited by the antenna design. At lower optical powers we reveal a saturation level in the NEP of 3.8×10-19W/Hz1/2, competitive with other detectors for this purpose and the lowest optical NEP so far for MKIDs. The noise over the entire power range is limited by photon- and generation-recombination noise, the fundamental noise sources for these detectors.

DOI: 10.1109/irmmw-thz.2014.6956151

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