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arXiv · 2411.12782

Multiplexed readout of Superconductor--Normal-Conductor--Superconductor bolometers

Priyank Singh·András Gunyhó·Heikki Suominen·Giacomo Catto·Florian Blanchet·Qi-Ming Chen·Arman Alizadeh·Aarne Keränen·Jian Ma·Timm Mörstedt·Wei Liu·Mikko Möttonen
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Abstract

Recently, ultrasensitive calorimeters have been proposed as a resource-efficient solution for multiplexed qubit readout in superconducting large-scale quantum processors. However, experiments demonstrating frequency multiplexing of these superconductor--normal--conductor--superconductor (SNS) sensors are are lacking in the literature. To this end, we present the design, fabrication, and operation of three SNS sensors with frequency-multiplexed input and probe circuits, all on a single chip. These devices have their probe frequencies in the range 150 MHz--200 MHz, which is well detuned from the heater frequencies of 4.4 GHz--7.6 GHz compatible with typical readout frequencies of superconducting qubits. Importantly, we show on-demand triggering of both individual and multiple low-noise SNS bolometers with very low cross talk. These experiments pave the way for multiplexed bolometric characterization and calorimetric readout of multiple qubits, a promising step in minimizing related resources such as the number of readout lines and microwave isolators in large-scale superconducting quantum computers.

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Priyank Singh, András Gunyhó, Heikki Suominen, Giacomo Catto, Florian Blanchet, Qi-Ming Chen, Arman Alizadeh, Aarne Keränen, Jian Ma, Timm Mörstedt, Wei Liu, Mikko Möttonen. 2024-11-19. Multiplexed readout of Superconductor--Normal-Conductor--Superconductor bolometers. https://arxiv.org/abs/2411.12782

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