Skip to main content

Research Repository

Advanced Search

All Outputs (3)

Maximum violations of the quantum-witness equality (2015)
Journal Article
Schild, G., & Emary, C. (2015). Maximum violations of the quantum-witness equality. Physical review. A, 92(3), 1-6. https://doi.org/10.1103/PhysRevA.92.032101

We consider the quantum-witness test of macroscopic realism and derive an upper bound for possible violations of this equality due to quantum mechanics. The bound depends only on the number of possible outcomes for the blind measurement at the heart... Read More about Maximum violations of the quantum-witness equality.

Time-delayed feedback control of the Dicke-Hepp-Lieb superradiant quantum phase transition (2015)
Journal Article
Kopylov, W., Emary, C., Schöll, E., & Brandes, T. (2015). Time-delayed feedback control of the Dicke-Hepp-Lieb superradiant quantum phase transition. New Journal of Physics, 17(1), 013040. https://doi.org/10.1088/1367-2630/17/1/013040

We apply the time-delayed Pyragas control scheme to the dissipative Dicke model via a modulation of the atom-field-coupling. The feedback creates an infinite sequence of non-equilibrium phases with fixed points and limit cycles in the primary superra... Read More about Time-delayed feedback control of the Dicke-Hepp-Lieb superradiant quantum phase transition.

Ideal negative measurements in quantum walks disprove theories based on classical trajectories (2015)
Journal Article
Robens, C., Alt, W., Meschede, D., Emary, C., & Alberti, A. (2015). Ideal negative measurements in quantum walks disprove theories based on classical trajectories. Physical Review X, 5(1), Article 011003. https://doi.org/10.1103/PhysRevX.5.011003

We report on a stringent test of the nonclassicality of the motion of a massive quantum particle, which propagates on a discrete lattice. Measuring temporal correlations of the position of single atoms performing a quantum walk, we observe a 6σ viola... Read More about Ideal negative measurements in quantum walks disprove theories based on classical trajectories.