W. Vogel

Time correlations in atmospheric quantum channels

M. Klen, Dmytro Vasylyev, W. Vogel, А. А. Семенов

Efficient transfer of quantum information between remote parties is a crucial challenge for quantum communication over atmospheric channels. Random fluctuations of the channel transmittance are a major disturbing factor for its practical implementation. We study correlations between channel transmittances at different moments …

ua, de (code pays fourni par la source)

Photocounting measurements with dead time and afterpulses in the continuous-wave regime

А. А. Семенов, J. Samelin, Chris Boldt, Melanie Schünemann et autres

The widely used experimental technique of continuous-wave detection assumes counting pulses of photocurrent from a click-type detector inside a given measurement time window. With such a procedure we miss out the photons detected after each photocurrent pulse during the detector dead time. …

ua, de (code pays fourni par la source)

Time correlations in atmospheric quantum channels

M. Klen, Dmytro Vasylyev, W. Vogel, А. А. Семенов

Efficient transfer of quantum information between remote parties is a crucial challenge for quantum communication over atmospheric channels. Random fluctuations of the channel transmittance are a major disturbing factor for its practical implementation. We study correlations between channel transmittances at different moments …

ua, de (code pays fourni par la source)

Photocounting measurements with dead time and afterpulses in the continuous-wave regime

А. А. Семенов, J. Samelin, Chris Boldt, Melanie Schünemann et autres

The widely used experimental technique of continuous-wave detection assumes counting pulses of photocurrent from a click-type detector inside a given measurement time window. With such a procedure we miss out the photons detected after each photocurrent pulse during the detector dead time. …

ua, de (code pays fourni par la source)

Nonclassical correlations of radiation in relation to Bell nonlocality

V. S. Kovtoniuk, I. S. Yeremenko, S. Ryl, W. Vogel et autres

We analyze nonclassical correlations between outcomes of measurements conducted on two spatial radiation modes. These correlations cannot be simulated with statistical mixtures of coherent states or, more generally, with non-negative phase-space functions of quantum states and measurements. We argue that nonclassical correlations …

ua, de (code pays fourni par la source)

Nonclassical correlations of radiation in relation to Bell nonlocality

V. S. Kovtoniuk, I. S. Yeremenko, S. Ryl, W. Vogel et autres

We analyze nonclassical correlations between outcomes of measurements conducted on two spatial radiation modes. These correlations cannot be simulated with statistical mixtures of coherent states or, more generally, with non-negative phase-space functions of quantum states and measurements. We argue that nonclassical correlations …

ua, de (code pays fourni par la source)

Gaussian versus Non-Gaussian Filtering of Phase-Insensitive Nonclassicality

Barbara Kühn, W. Vogel, Valérian Thiel, Sofiane Merkouche et autres

Measures of quantum properties are essential to understanding the fundamental differences between quantum and classical systems as well as quantifying resources for quantum technologies. Here, two broad classes of bosonic phase-space functions, which are filtered versions of the Glauber-Sudarshan P function, are …

de, us, gb (code pays fourni par la source)

Quantum Correlations beyond Entanglement and Discord

S. Köhnke, Elizabeth Agudelo, Melanie Schünemann, O. Schlettwein et autres

Dissimilar notions of quantum correlations have been established, each being motivated through particular applications in quantum information science and each competing for being recognized as the most relevant measure of quantumness. In this contribution, we experimentally realize a form of quantum correlation …

de, at (code pays fourni par la source)

Detector-Agnostic Phase-Space Distributions

Jan Sperling, David S. Phillips, Jacob F. F. Bulmer, Guillaume Thekkadath et autres

The representation of quantum states via phase-space functions constitutes an intuitive technique to characterize light. However, the reconstruction of such distributions is challenging as it demands specific types of detectors and detailed models thereof to account for their particular properties and imperfections. …

de, gb, us (code pays fourni par la source)

Soziale Arbeit in der Geriatrie

W. Vogel

Quasiprobability distributions for quantum-optical coherence and beyond

Jan Sperling, W. Vogel

Abstract We study the quasiprobability representation of quantum light, as introduced by Glauber and Sudarshan, for the unified characterization of quantum phenomena. We begin with reviewing the past and current impact of this technique. Regularization and convolution methods are specifically considered since …

de (code pays fourni par la source)

Accessing the non-equal-time commutators of a trapped ion

F. Krumm, W. Vogel

The vibronic dynamics of a trapped ion in the resolved-sideband regime can be described by the explicitly time-dependent nonlinear Jaynes-Cummings model. It is shown that the expectation value of the interaction Hamiltonian and its non-equal-time commutator can be determined by measuring the …

de (code pays fourni par la source)