187 citations · 1.1k across the 45 of their papers we have counts for
35 papers · 1 filter
Energy-time entanglement from a resonantly driven quantum dot three-level system
M. Hohn, K. Barkemeyer, M. von Helversen +8
Entanglement is a major resource in advanced quantum technology, where it can enable secure exchange of information over large distances. Energy-time entanglement is particularly a…
Heisenberg treatment of multiphoton pulses in waveguide QED with time-delayed feedback
Kisa Barkemeyer, Andreas Knorr, Alexander Carmele
The dynamics of waveguide-QED systems involving coherent time-delayed feedback give rise to a hierarchy of multi-time correlations within the Heisenberg picture due to the induced…
Efficient bit encoding of neural networks for Fock states
Oliver Kästle, Alexander Carmele
We present a bit encoding scheme for a highly efficient and scalable representation of bosonic Fock number states in the restricted Boltzmann machine neural network architecture. I…
Boosting energy-time entanglement using coherent time-delayed feedback
Kisa Barkemeyer, Marcel Hohn, Stephan Reitzenstein +1
The visibility of the two-photon interference in the Franson interferometer serves as a measure of the energy-time entanglement of the photons. We propose to control the visibility…
Sampling asymmetric open quantum systems for artificial neural networks
Oliver Kästle, Alexander Carmele
While established neural network approaches based on restricted Boltzmann machine architectures and Metropolis sampling methods are well suited for symmetric open quantum systems,…
Continuous and time-discrete non-Markovian system-reservoir interactions: Dissipative coherent quantum feedback in Liouville space
Oliver Kästle, Regina Finsterhoelzl, Andreas Knorr +1
Based on tensor network realizations of path integrals reducing exponential memory scaling to polynomial efficiency and a Liouville space implementation of a time-discrete quantum…
Strongly entangled system-reservoir dynamics with multiphoton pulses beyond the two-excitation limit: Exciting the atom-photon bound state
Kisa Barkemeyer, Andreas Knorr, Alexander Carmele
Within the matrix product state framework, we study the non-Markovian feedback dynamics of a two-level system interacting with the electromagnetic field inside a semi-infinite wave…
Unidirectional Quantum Transport in Optically Driven -type Quantum Dot Chains
Oliver Kaestle, Emil Vosmar Denning, Jesper Mørk +2
We predict a mechanism for achieving complete population inversion in a continuously driven InAs/GaAs semiconductor quantum dot featuring -type transitions. This highly nonequil…
Memory-Critical Dynamical Buildup of Phonon-Dressed Majorana Fermions
Oliver Kästle, Ying Hu, Alexander Carmele
We investigate the dynamical interplay between topological state of matter and a non-Markovian dissipation, which gives rise to a new and crucial time scale into the system dynamic…
Non-equilibrium non-Markovian steady-states in open quantum many-body systems: Persistent oscillations in Heisenberg quantum spin chains
Regina Finsterhölzl, Manuel Katzer, Alexander Carmele
We investigate the effect of a non-Markovian, structured reservoir on an open Heisenberg spin chain. We establish a coherent self-feedback mechanism as the reservoir couples freque…
Feedback-induced instabilities and dynamics in the Jaynes-Cummings model
Nikolett Német, Scott Parkins, Victor Canela +1
We investigate the coherence and steady-state properties of the Jaynes-Cummings model subjected to time-delayed coherent feedback in the regime of multiple excitations. The introdu…
Long-range interaction in an open boundary-driven Heisenberg spin lattice: A far-from-equilibrium transition to ballistic transport
Manuel Katzer, Willy Knorr, Regina Finsterhölzl +1
We study an open Heisenberg XXZ spin chain with long-range Ising-type interaction, which is incoherently driven at its boundaries and therefore a far-from-equilibrium steady state…
A quantum optical realization of the Ornstein-Uhlenbeck process via simultaneous action of white noise and feedback
Alexander Carmele, Scott Parkins, Andreas Knorr
We establish an important connection between coherent quantum feedback and the Ornstein-Uhlenbeck process in quantum optics. We show that an emitter with fluctuating energy levels…
A Hahn-Ramsey Scheme for Dynamical Decoupling and DC Magnetometry with Single Solid-State Qubits
Nikola Sadzak, Alexander Carmele, Claudia Widmann +3
Spin systems in solid state materials are promising qubit candidates for quantum information or quantum sensing. A major prerequisite here is the coherence of spin phase oscillatio…
Pronounced non-Markovian features in multiply-excited, multiple-emitter waveguide-QED: Retardation-induced anomalous population trappin
Alexander Carmele, Nikolett Nemet, Victor Canela +1
The Markovian approximation is widely applied in the field of quantum optics due to the weak frequency dependence of the vacuum field amplitude, and in consequence non-Markovian ef…
Revisiting Quantum Feedback Control: Disentangling the Feedback-induced Phase from the Corresponding Amplitude
Kisa Barkemeyer, Regina Finsterhölzl, Andreas Knorr +1
Coherent time-delayed feedback allows the control of a quantum system and its partial stabilization against noise and decoherence. The crucial and externally accessible parameters…
Non-Markovian features in semiconductor quantum optics: Quantifying the role of phonons in experiment and theory
Alexander Carmele, Stephan Reitzenstein
We discuss phonon-induced non-Markovian and Markovian features in QD-based optics. We cover lineshapes in linear absorption experiments, phonon-induced incoherence in the Heitler r…
Comparison between continuous- and discrete-mode coherent feedback for the Jaynes-Cummings model
Nikolett Német, Alexander Carmele, Scott Parkins +1
Using the example of the Jaynes-Cummings model, we present a comparison between time-delayed coherent feedback mediated by reservoirs with continuous and discrete mode structures a…
Stabilizing a discrete time crystal against dissipation
Leon Droenner, Regina Finsterhölzl, Markus Heyl +1
Eigenstate phases such as the discrete time crystal exhibit an inherent instability upon the coupling to an environment, which restores equipartition of energy and therefore acts a…
Stabilizing quantum coherence against pure dephasing in the presence of quantum feedback at finite temperature
Nikolett Német, Scott Parkins, Andreas Knorr +1
A general formalism to describe the dynamics of quantum emitters in structured reservoirs is introduced. As an application, we investigate the optical coherence of an atom-like emi…
Quantum Pyragas control: Selective-control of individual photon probabilities
Leon Droenner, Nicolas L. Naumann, Eckehard Schöll +2
Pyragas control allows to stabilize unstable states in applied nonlinear science. We propose to apply a quantum version of the Pyragas protocol to control individual photon-probabi…
Correlations of cascaded photons: An analytical study in the two-photon Mollow regime
Alexander Carmele, Samir Bounouar, Max Strauß +2
Mollow physics in the two-photon regime shows interesting features such as path-controlled time-reordering of photon pairs without the need to delay them. Here, we calculate analyt…
Quantum cascade driving: Dissipatively mediated coherences
Shahabedin C. Azizabadi, Nicolas L. Naumann, Manuel Katzer +2
Quantum cascaded systems offer the possibility to manipulate a target system with the quantum state of a source system. Here, we study in detail the differences between a direct qu…
Collective enhancements in many-emitter phonon lasing
Leon Droenner, Nicolas L. Naumann, Julia Kabuss +1
We investigate theoretically the many-emitter phonon laser based on optically driven semiconductor quantum dots within an acoustic nanocavity. We map the phonon laser Hamiltonian t…