Radio-frequency electron cascade in semiconductor quantum dots

Authors:Tara Murphy, Lorenzo Peri, Giovanni A. Oakes, Jacob F. Chittock-Wood, Ross C. C. Leon, Fabrizio Berritta, Amber Heskes, David Wise, Anasua Chatterjee, Ferdinand Kuemmeth, M. Fernando Gonzalez-Zalba

Abstract:Electron cotunneling in semiconductor quantum dots is a higher-order tunneling mechanism that connects initial and final charge states through energetically inaccessible virtual intermediate configurations. In quantum-dot arrays, such processes can produce simultaneous charge motion across multiple tunnel junctions and enable transitions that would otherwise be suppressed by Coulomb blockade. Here, building on an earlier proof-of-principle demonstration, we investigate radio-frequency (rf)-driven correlated cotunneling and its application to dispersive quantum-dot readout. Using both theoretical modeling and experimental measurements in two different foundry-fabricated silicon devices, we show that an external rf drive can induce correlated cyclic single-electron transitions, resulting in enhanced charge-polarization of the system. We develop a general theoretical framework for rf electron-cascade readout, which exploits cotunneling events in quantum-dot systems with three or more dots to produce a relative signal enhancement, and extend its experimental demonstration to a gate-sensed device architecture. Our results establish the operating principles of rf electron-cascade readout and provide a route to increased dispersive readout fidelity in semiconductor quantum computing architectures.

Mesoscale and Nanoscale Physics (cond-mat.mes-hall); Quantum Physics (quant-ph)

arXiv:2610.05206 [cond-mat.mes-hall]

(or arXiv:2610.05206v1 [cond-mat.mes-hall] for this version)

https://doi.org/10.48550/arXiv.2610.05206 arXiv-issued DOI via DataCite (pending registration)