| Autor: |
Dyte HE; Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom., Gillard G; Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom., Manna S; Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz, Altenberger Strasse 69, 4040 Linz, Austria., Covre da Silva SF; Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz, Altenberger Strasse 69, 4040 Linz, Austria., Rastelli A; Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz, Altenberger Strasse 69, 4040 Linz, Austria., Chekhovich EA; Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom.; Department of Physics and Astronomy, University of Sussex, Brighton BN1 9QH, United Kingdom. |
| Abstrakt: |
The measurement problem dates back to the dawn of quantum mechanics. Here, we measure a quantum dot electron spin qubit through off-resonant coupling with a highly redundant ancilla, consisting of thousands of nuclear spins. Large redundancy allows for single-shot measurement with high fidelity ≈99.85%. Repeated measurements enable heralded initialization of the qubit and backaction-free detection of electron spin quantum jumps, attributed to burstlike fluctuations in a thermally populated phonon bath. Based on these results we argue that the measurement, linking quantum states to classical observables, can be made without any "wave function collapse" in agreement with the Quantum Darwinism concept. |
