86 citations · 460 across the 20 of their papers we have counts for
20 papers
Exact calculation of entanglement negativity for a 1+1D massless scalar field using phase space methods
Jason Pye, Atharva Hingane, Robert H. Jonsson
Quantum fields exhibit a rich entanglement structure which is still not fully understood. In this work, we study the entanglement structure of the vacuum state of a massless scalar…
The negativity core of a 1+1D massless scalar quantum field
Jason Pye, Atharva Hingane, Robert H. Jonsson
Vacuum entanglement is a fundamental feature of quantum field theory exhibiting rich structure that is not completely understood. Here, we provide a complete characterization of th…
Non-Exponential Decay in Finite Photonic Waveguide Arrays
Florian H. Huber, Benedikt Braumandl, Johannes Knörzer +5
Open quantum-system dynamics can follow exponential decay, non-exponential relaxation, or oscillatory dynamics, depending on the system-environment coupling. We study a lattice wit…
Geometric speed limit of state preparation and curved control spaces
Maximilian Goll, Robert H. Jonsson
The preparation of quantum many-body systems faces the difficulty that in a realistic scenario only few control parameters of the system may be accessible. In this context, an inte…
Random pure Gaussian states and Hawking radiation
Erik Aurell, Lucas Hackl, Paweł Horodecki +2
A black hole evaporates by Hawking radiation. Each mode of that radiation is thermal. If the total state is nevertheless to be pure, modes must be entangled. Estimating the minimum…
Chain-mapping methods for relativistic light-matter interactions
Robert H. Jonsson, Johannes Knörzer
The interaction between localized emitters and quantum fields, both in relativistic settings and in the case of ultra-strong couplings, requires non-perturbative methods beyond the…
Lensing of Vacuum Entanglement near Schwarzschild Black Holes
João G. A. Caribé, Robert H. Jonsson, Marc Casals +2
An important feature of Schwarzschild spacetime is the presence of orbiting null geodesics and caustics. Their presence implies strong gravitational lensing effects for matter and…
Gaussian quantum estimation of the lossy parameter in a thermal environment
Robert Jonsson, Roberto Di Candia
Lossy bosonic channels play an important role in a number of quantum information tasks, since they well approximate thermal dissipation in an experiment. Here, we characterize thei…
Non-perturbative treatment of giant atoms using chain transformations
David D. Noachtar, Johannes Knörzer, Robert H. Jonsson
Superconducting circuits coupled to acoustic waveguides have extended the range of phenomena that can be experimentally studied using tools from quantum optics. In particular giant…
Supersymmetric Free Fermions and Bosons: Locality, Symmetry and Topology
Zongping Gong, Robert H. Jonsson, Daniel Malz
Supersymmetry, originally proposed in particle physics, refers to a dual relation that connects fermionic and bosonic degrees of freedom in a system. Recently, there has been consi…
Entanglement dualities in supersymmetry
Robert H. Jonsson, Lucas Hackl, Krishanu Roychowdhury
We derive a general relation between the bosonic and fermionic entanglement in the ground states of supersymmetric quadratic Hamiltonians. For this, we construct canonical identifi…
A comparison between quantum and classical noise radar sources
Robert Jonsson, Roberto Di Candia, Martin Ankel +2
We compare the performance of a quantum radar based on two-mode squeezed states with a classical radar system based on correlated thermal noise. With a constraint of equal number o…
Communication through quantum fields near a black hole
Robert H. Jonsson, David Q. Aruquipa, Marc Casals +2
We study the quantum channel between two localized first-quantized systems that communicate in 3+1 dimensional Schwarzschild spacetime via a quantum field. We analyze the informati…
Minimal energy cost of entanglement extraction
Lucas Hackl, Robert H. Jonsson
We compute the minimal energy cost for extracting entanglement from the ground state of a bosonic or fermionic quadratic system. Specifically, we find the minimal energy increase $…
General no-go theorem for entanglement extraction
Petar Simidzija, Robert H. Jonsson, Eduardo Martin-Martinez
We study under what circumstances a separable bipartite system A-B can or cannot become entangled through local interactions with a bi-local entangled source -$\text{S}…
Transmitting qubits through relativistic fields
Robert H. Jonsson, Katja Ried, Eduardo Martin-Martinez +1
Wireless communication derives its power from the simultaneous emission of signals in multiple directions. However, in the context of quantum communication, this phenomenon must be…
Quantum Signaling in Relativistic Motion and Across Acceleration Horizons
Robert H. Jonsson
The quantum channel between two particle detectors provides a prototype framework for the study of wireless quantum communication via relativistic quantum fields. In this article w…
Information travels in massless fields in 1+1 dimensions where energy cannot
Robert H. Jonsson
It has been demonstrated that, in (1+1) spacetime dimensions, massless fields can be used for information transmission even between parties that are time-like rather than light-lik…
Information transmission without energy exchange
Robert H. Jonsson, Eduardo Martin-Martinez, Achim Kempf
We show that it is possible to use a massless field in the vacuum to communicate in such a way that the signal travels arbitrarily slower than the speed of light and such that no e…
Quantum signalling in cavity QED
Robert H. Jonsson, Eduardo Martin-Martinez, Achim Kempf
We consider quantum signalling between two-level quantum systems in a cavity, in the pertubative regime of the earliest possible arrival times of the signal. We present two main re…