The Relevance of Non-Sequential Time

Hans Primas

J. Lang, A. Ruh

Patrick Lima

In this work, we develop the details of experimental proposals for the verification of non-contextual inequalities in qutrits through sequential measurements using photonic circuits as physical platforms for implementing states and observables. Initially, an introduction to the concept of quantum contextuality and the relevance of non-contextuality inequalities was carried out. We explained the details of performing sequential measurements and the reason they were chosen as an experimental method as well as the details of the choice of photonic circuits as an experimental plataform to realize the experiments. Finally, we obtained the photonic circuit designs, and their respective experimental parameters, capable of performing non-contextuality tests through the observation of state-dependent and state-independent non-contextuality inequalities in three-level systems.

Rudolf Hilfer A

Junxiang Zhang, Yuan-De Jin, Chu-Dan Qiu +2 more

Abstract Metastability is a ubiquitous phenomenon in non-equilibrium physics and classical stochastic dynamics. It arises when the system dynamics settles in long-lived states before eventually decaying to true equilibria. Remarkably, it has been predicted that quantum metastability can also occur in continuous-time and discrete-time open quantum dynamics. However, the direct experimental observation of metastability in open quantum systems has remained elusive. Here, we experimentally observe metastability in the discrete-time evolution of a single nuclear spin in diamond, realized by sequential Ramsey interferometry measurements of a nearby nitrogen-vacancy electron spin. We demonstrate that the metastable polarization of the nuclear spin emerges at around 60,000∼250,000 sequential measurements, enabling high-fidelity single-shot readout of the nuclear spin. Our results represent a concrete step towards uncovering non-equilibrium physics in open quantum dynamics, which is practically relevant for the utilization of metastable information for various quantum information processing tasks.

D. Bollé