2020/10/09 by Michael S. Ferguson, Leon C. Camenzind, Ferguson, Michael S. +13 · 1 citation
Computer Science · Physics and Astronomy · #FOS: Physical sciences #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum and electron transport phenomena
paper · pdf · doi:10.48550/arxiv.2010.04635
openalex publication_date 2020/10/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The current revolution in quantum technologies relies on the ability to isolate, coherently control, and measure the state of quantum systems. The act of measurement in quantum mechanics, however, is naturally invasive as the measurement apparatus becomes entangled with the system that it observes. Even for ideal detectors, the measurement outcome always leads to a disturbance in the observed system, a phenomenon called quantum measurement backaction. Here we report a profound change in the many-body properties of the measured system due to quantum measurements. We observe this backaction-induced transition in a mesoscopic double quantum-dot in the Coulomb-blockade regime, where we switch the electron population through measurement with a charge sensor dot. Our finding showcases the important changes in behaviour that can arise due to quantum detectors, which are ubiquitous in quantum technologies.