Condensed Matter Physics Seminar
Speaker: Kater Murch, Washington University, St. Louis
Title: Measurement and control in superconducting qubits: from the quantum Zeno effect to quantum enhanced metrology
Refreshments available at 3:45 pm.
Date: Mon, 16 Oct 2017, 4:10 pm – 5:10 pm
Location: 1400 BPS Bldg.
The quantum Zeno effect is a feature of measurement-driven quantum evolution where frequent measurement inhibits the decay of a quantum state. We will explore how the opposite effect; the anti-Zeno effect – where frequent measurement accelerates decay – can also emerge from frequent measurement. The emergence of one effect or the other elucidates the nature of quantum measurement and the role measurement plays in controlling quantum evolution. In a second experiment, we investigate how control over a single qubit can be used achieve a quantum speedup in the precision of frequency measurements, demonstrating a frequency sensitivity that improves as 1/T2, where T is the duration of the experiment.