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arXiv:2607.14559

Dispersive Readout of a SiMOS Quantum Dot Using a Flip-Chip Integrated Microwave Resonator

Vo Kim Hieu Van, Santiago Serrano, Cédric Bohémier, Ajit Dash, Fay E. Hudson, Tuomo Tanttu, Chih Hwan Yang, MengKe Feng, Ensar Vahapoglu, Florian K. Unseld, Wee Han Lim, Andrea Morello, Andrew S. Dzurak, K. W. Chan

Published Jul 16, 2026• 0 citations
arXivHTMLPDF

Abstract

Heterogeneous integration provides a promising route to combine semiconductor quantum dot devices and superconducting microwave circuits, while allowing each component to be fabricated using an optimized process flow. Here, we demonstrate a flip-chip integrated platform for dispersive readout of silicon metal-oxide semiconductor (SiMOS) quantum dot devices. A SiMOS double quantum dot chip is bonded to a superconducting aluminum resonator chip using indium bump interconnects to enable microwave coupling to the quantum dot gate. We show that the developed flip-chip process is compatible with cryogenic operation of both the SiMOS device and the superconducting resonator, and demonstrate resonator-based detection of charge transitions in the quantum dot system. The readout signal-to-noise ratio follows a dependence of $\sqrt{t}$ with the integration time, reaching SNR = 1 at an integration time of approximately 0.3 ms. These results establish flip-chip bonding as a viable integration approach for SiMOS quantum dot devices operating at both dc and microwave frequencies, with potential applications for resonator-based techniques such as spin-photon coupling.

DOI
10.48550/arxiv.2607.14559

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