273 citations · 963 across the 18 of their papers we have counts for
19 papers
Dynamically Generated Synthetic Electric Fields for Photons
Petr Zapletal, Stefan Walter, Florian Marquardt
Static synthetic magnetic fields give rise to phenomena including the Lorentz force and the quantum Hall effect even for neutral particles, and they have by now been implemented in…
General linearized theory of quantum fluctuations around arbitrary limit cycles
Carlos Navarrete-Benlloch, Talitha Weiss, Stefan Walter +1
The theory of Gaussian quantum fluctuations around classical steady states in nonlinear quantum-optical systems (also known as standard linearization) is a cornerstone for the anal…
Synchronization of an optomechanical system to an external drive
Ehud Amitai, Niels Lörch, Andreas Nunnenkamp +2
Optomechanical systems driven by an effective blue detuned laser can exhibit self-sustained oscillations of the mechanical oscillator. These self-oscillations are a prerequisite fo…
Quantum-coherent phase oscillations in synchronization
Talitha Weiss, Stefan Walter, Florian Marquardt
Recently, several studies have investigated synchronization in quantum-mechanical limit-cycle oscillators. However, the quantum nature of these systems remained partially hidden, s…
Lifting the Franck-Condon blockade in driven quantum dots
Patrick Haughian, Stefan Walter, Andreas Nunnenkamp +1
Electron-vibron coupling in quantum dots can lead to a strong suppression of the average current in the sequential tunneling regime. This effect is known as Franck-Condon blockade…
Non local quantum state engineering with the Cooper pair splitter beyond the Coulomb blockade regime
Ehud Amitai, Rakesh P. Tiwari, Stefan Walter +2
A Cooper pair splitter consists of two quantum dots side-coupled to a conventional superconductor. Usually, the quantum dots are assumed to have a large charging energy compared to…
Classical Dynamical Gauge Fields in Optomechanics
Stefan Walter, Florian Marquardt
Artificial gauge fields for neutral particles such as photons, recently attracted a lot of attention in various fields ranging from photonic crystals to ultracold atoms in optical…
Detecting nonlocal Cooper pair entanglement by optical Bell inequality violation
Simon E. Nigg, Rakesh P. Tiwari, Stefan Walter +1
Based on the Bardeen Cooper Schrieffer (BCS) theory of superconductivity, the coherent splitting of Cooper pairs from a superconductor to two spatially separated quantum dots has b…
Quantum synchronization of two Van der Pol oscillators
Stefan Walter, Andreas Nunnenkamp, Christoph Bruder
We study synchronization of two dissipatively coupled Van der Pol oscillators in the quantum regime. Due to quantum noise strict frequency locking is absent and is replaced by a cr…
Teleportation-induced entanglement of two nanomechanical oscillators coupled to a topological superconductor
Stefan Walter, Jan Carl Budich
A one-dimensional topological superconductor features a single fermionic zero mode that is delocalized over two Majorana bound states located at the ends of the system. We study a…
Transport properties of double quantum dots with electron-phonon coupling
Stefan Walter, Björn Trauzettel, Thomas L. Schmidt
We study transport through a double quantum dot system in which each quantum dot is coupled to a phonon mode. Such a system can be realized, e.g., using a suspended carbon nanotube…
Quantum synchronization of a driven self-sustained oscillator
Stefan Walter, Andreas Nunnenkamp, Christoph Bruder
Synchronization is a universal phenomenon that is important both in fundamental studies and in technical applications. Here we investigate synchronization in the simplest quantum-m…
Entanglement of nanoelectromechanical oscillators by Cooper-pair tunneling
Stefan Walter, Jan Carl Budich, Jens Eisert +1
We demonstrate that entanglement of two macroscopic nanoelectromechanical resonators -- coupled to each other via a common detector, a tunnel junction -- can be generated by runnin…
Direct and charge transfer mediated photogeneration in polymer-fullerene bulk heterojunction solar cells
Markus Mingebach, Stefan Walter, Vladimir Dyakonov +1
We investigated photogeneration yield and recombination dynamics in blends of poly(3-hexyl thiophene) (P3HT) and poly[2-methoxy-5-(30,70-dimethyloctyloxy)-1,4-phenylenevinylene] (M…
Failure of protection of Majorana based qubits against decoherence
Jan Carl Budich, Stefan Walter, Bjoern Trauzettel
Qubit realizations based on Majorana bound states have been considered promising candidates for quantum information processing which is inherently inert to decoherence. We put the…
Detecting Majorana Bound States by Nanomechanics
Stefan Walter, Thomas L. Schmidt, Kjetil Børkje +1
We propose a nanomechanical detection scheme for Majorana bound states, which have been predicted to exist at the edges of a one-dimensional topological superconductor, implemented…
Momentum and position detection in nanoelectromechanical systems beyond Born and Markov approximations
Stefan Walter, Björn Trauzettel
We propose and analyze different schemes to probe the quantum nature of nanoelectromechanical systems (NEMS) by a tunnel junction detector. Using the Keldysh technique, we are able…
Positivity of the two-dimensional Brown-Ravenhall operator
Stefan Walter
We determine the critical coupling of the two-dimensional Brown-Ravenhall operator with Coulomb potential. Boundedness from below has essentially been proven by Bouzouina, whose wo…
Bloch oscillations in lattice potentials with controlled aperiodicity
Stefan Walter, Dominik Schneble, Adam C. Durst
We numerically investigate the damping of Bloch oscillations in a one-dimensional lattice potential whose translational symmetry is broken in a systematic manner, either by making…