869 citations · 10.9k across the 170 of their papers we have counts for
164 papers · 1 filter
Multinegativity and single-letter formulas for asymptotic entanglement
Raphael Brinster, Tulja Varun Kondra, Hermann Kampermann +2
The study of entanglement inevitably leads to the concept of regularization, where measures are evaluated on infinitely many copies of a state. Single-letter formulas try to make t…
Sharp Quantum Capacity Thresholds: Exponential Strong Converses for Degradable and Antidegradable Channels
Tulja Varun Kondra, Raphael Brinster, Hermann Kampermann +2
The quantum capacity of a noisy channel quantifies the maximum rate at which quantum information can be transmitted reliably. For general channels, its evaluation requires an optim…
Very Strong Irreversibility of Quantum Entanglement
Tulja Varun Kondra, Raphael Brinster, Hermann Kampermann +2
The manipulation of quantum entanglement is fundamentally irreversible: some mixed entangled states require pure entanglement for their preparation, although no pure entanglement c…
Fundamental limitations on entanglement extraction from purity
Tulja Varun Kondra, Pedro Barrios Hita, Justus Neumann +2
States of sufficiently low purity are separable and cannot be entangled by unital (purity-non-generating) operations. Since high-purity states are experimentally demanding, it is n…
The relative entropy of magic and its nonadditivity
Carolin Deckers, Justus Neumann, Hermann Kampermann +1
In most stabilizer-based quantum computing schemes, so-called magic states are a necessary resource for implementing non-transversal quantum gates. With the resource theory of magi…
Bounds on quantum conference key agreement in pair-entangled networks
Justus Neumann, Hermann Kampermann, Dagmar Bruß +1
We investigate the task of conference key agreement in near-term quantum networks, where the nodes are connected by sources of bipartite entangled states, under the class of local…
Quantum Hypergraph States: A Review
Davide Poderini, Dagmar Bruß, Chiara Macchiavello
Quantum hypergraph states extend the well-studied class of graph states by taking into account multi-qubit interactions through hyperedges. They provide a powerful framework to rep…
Robust certification of non-projective measurements: theory and experiment
Raphael Brinster, Peter Tirler, Shishir Khandelwal +7
Determining the conditions under which positive operator-valued measures (POVMs), the most general class of quantum measurements, outperform projective measurements remains a chall…
Maximally non-projective measurements are not always symmetric informationally complete
Gabriele Cobucci, Raphael Brinster, Shishir Khandelwal +4
Standard quantum measurements are projective. However, the full scope of quantum measurements is represented by positive operator-valued measures (POVMs) and many of these break th…
Spanning-tree-packing protocol for conference key propagation in quantum networks
Anton Trushechkin, Hermann Kampermann, Dagmar Bruß
We consider a network of users connected by pairwise quantum key distribution (QKD) links. Using these pairwise secret keys and public classical communication, the users want to ge…
Multiplexed multipartite quantum repeater rates in the stationary regime
Julia A. Kunzelmann, Anton Trushechkin, Nikolai Wyderka +2
Multipartite quantum repeaters play an important role in quantum communication networks enabling the transmission of quantum information over larger distances. To increase the rate…
No quantum advantage without classical communication: fundamental limitations of quantum networks
Justus Neumann, Tulja Varun Kondra, Kiara Hansenne +5
Quantum networks connect systems at separate locations via quantum links, enabling a wide range of quantum information tasks between distant parties. Large-scale networks have the…
Quantum mechanics based on real numbers: A consistent description
Pedro Barrios Hita, Anton Trushechkin, Hermann Kampermann +2
Complex numbers play a crucial role in quantum mechanics. However, their necessity remains debated: whether they are fundamental or merely convenient. Recently, it was shown that a…
High-dimensional quantum key distribution rates for multiple measurement bases
Nikolai Wyderka, Giovanni Chesi, Hermann Kampermann +2
We investigate the advantages of high-dimensional encoding for a quantum key distribution protocol. In particular, we address a BBM92-like protocol where the dimension of the syste…
High-dimensional quantum key distribution with resource-efficient detection
Maciej Ogrodnik, Adam Widomski, Dagmar Bruß +7
While quantum key distribution (QKD) based on two-dimensional (qubit) encoding is a mature, field-tested technology, its performance is lacking for many cryptographic applications.…
Quantum Key Distribution with Basis-Dependent Detection Probability
Federico Grasselli, Giovanni Chesi, Nathan Walk +7
Quantum Key Distribution (QKD) is a promising technology for secure communication. Nevertheless, QKD is still treated with caution in certain contexts due to potential gaps between…
Multipartite multiplexing strategies for quantum routers
Julia A. Kunzelmann, Hermann Kampermann, Dagmar Bruß
This work explores the important role of quantum routers in communication networks and investigates the increase in efficiency using memories and multiplexing strategies. Motivated…
Bound entangled Bell diagonal states of unequal local dimensions, and their witnesses
Johannes Moerland, Nikolai Wyderka, Hermann Kampermann +1
Bell diagonal states constitute a well-studied family of bipartite quantum states that arise naturally in various contexts in quantum information. In this paper we generalize the n…
Steering witnesses for unknown Gaussian quantum states
Tatiana Mihaescu, Hermann Kampermann, Aurelian Isar +1
We define and fully characterize the witnesses based on second moments detecting steering in Gaussian states by means of Gaussian measurements. All such tests, which arise from lin…
Distributed quantum incompatibility
Lucas Tendick, Hermann Kampermann, Dagmar Bruß
Incompatible, i.e. non-jointly measurable quantum measurements are a necessary resource for many information processing tasks. It is known that increasing the number of distinct me…
Quantum Speed Limit for Change of Basis
Moein Naseri, Chiara Macchiavello, Dagmar Bruß +2
Quantum speed limits provide ultimate bounds on the time required to transform one quantum state into another. Here, we extend the notion of quantum speed limits to collections of…
Upper bound on the Guessing probability using Machine Learning
Sarnava Datta, Hermann Kampermann, Dagmar Bruß
The estimation of the guessing probability has paramount importance in quantum cryptographic processes. It can also be used as a witness for nonlocal correlations. In most of the s…
Continuity of robustness measures in quantum resource theories
Jonathan Schluck, Gláucia Murta, Hermann Kampermann +2
Robustness measures are increasingly prominent resource quantifiers that have been introduced for quantum resource theories such as entanglement and coherence. Despite the generali…
Construction of efficient Schmidt number witnesses for high-dimensional quantum states
Nikolai Wyderka, Giovanni Chesi, Hermann Kampermann +2
Recent progress in quantum optics has led to setups that are able to prepare high-dimensional quantum states for quantum information processing tasks. As such, it is of importance…