826 citations · 6.4k across the 112 of their papers we have counts for
65 papers · 1 filter
Quantum field heat engine powered by phonon-photon interactions
Alessandro Ferreri, Vincenzo Macrì, Frank K. Wilhelm +2
We present a quantum heat engine based on a cavity with two oscillating mirrors that confine a quantum field as the working substance. The engine performs an Otto cycle during whic…
Post-processing noisy quantum computations utilizing N-representability constraints
Tomislav Piskor, Florian G. Eich, Michael Marthaler +2
We propose and analyze a method for improving quantum chemical energy calculations on a quantum computer impaired by decoherence and shot noise. The error mitigation approach relie…
Mean-Field Approximate Optimization Algorithm
Aditi Misra-Spieldenner, Tim Bode, Peter K. Schuhmacher +3
The Quantum Approximate Optimization Algorithm (QAOA) is suggested as a promising application on early quantum computers. Here, a quantum-inspired classical algorithm, the mean-fie…
Two qubits in one transmon -- QEC without ancilla hardware
Alexander Simm, Shai Machnes, Frank K. Wilhelm
We show that it is theoretically possible to use higher energy levels for storing and controlling two qubits within a superconducting transmon. This is done by identifying energy l…
Problem-Size Independent Angles for a Grover-Driven Quantum Approximate Optimization Algorithm
David Headley, Frank K. Wilhelm
The Quantum Approximate Optimization Algorithm (QAOA) requires that circuit parameters are determined that allow one to sample from high-quality solutions to combinatorial optimiza…
Quantum optimal control in quantum technologies. Strategic report on current status, visions and goals for research in Europe
Christiane P. Koch, Ugo Boscain, Tommaso Calarco +8
Quantum optimal control, a toolbox for devising and implementing the shapes of external fields that accomplish given tasks in the operation of a quantum device in the best way poss…
Interplay between optomechanics and the dynamical Casimir effect
Alessandro Ferreri, Hannes Pfeifer, Frank K. Wilhelm +2
We develop a model of a quantum field confined within a cavity with a movable wall where the position of the wall is quantized. We obtain a full description of the dynamics of both…
Algorithm for initializing a generalized fermionic Gaussian state on a quantum computer
Michael P. Kaicher, Simon B. Jäger, Frank K. Wilhelm
We present explicit expressions for the central piece of a variational method developed by Shi et al. which extends variational wave functions that are efficiently computable on cl…
Integrated tool-set for Control, Calibration and Characterization of quantum devices applied to superconducting qubits
Nicolas Wittler, Federico Roy, Kevin Pack +6
Efforts to scale-up quantum computation have reached a point where the principal limiting factor is not the number of qubits, but the entangling gate infidelity. However, the highl…
Coupling a Superconducting Qubit to a Left-Handed Metamaterial Resonator
S. Indrajeet, H. Wang, M. D. Hutchings +4
Metamaterial resonant structures made from arrays of superconducting lumped circuit elements can exhibit microwave mode spectra with left-handed dispersion, resulting in a high den…
Self gravity decoheres quantum systems
Alessio Lapponi, Stefano Mancini, Frank K. Wilhelm +1
We study the effects of self gravity on the quantum state of a massive and static particle that initially contains quantum coherence between two positions. We employ linearized qua…
Quantum Simulation of a Discrete-Time Quantum Stochastic Walk
Peter K. Schuhmacher, Luke C. G. Govia, Bruno G. Taketani +1
Quantum walks have been shown to have a wide range of applications, from artificial intelligence, to photosynthesis, and quantum transport. Quantum stochastic walks (QSWs) generali…
An introduction into optimal control for quantum technologies
Frank K. Wilhelm, Susanna Kirchhoff, Shai Machnes +2
In this series of lectures, we would like to introduce the audience to quantum optimal control. The first lecture will cover basic ideas and principles of optimal control with the…
Leakage reduction in fast superconducting qubit gates via optimal control
Max Werninghaus, Daniel J. Egger, Federico Roy +3
Reaching high speed, high fidelity qubit operations requires precise control over the shape of the underlying pulses. For weakly anharmonic systems, such as superconducting transmo…
A superconducting detector that counts microwave photons up to two
Andrii M. Sokolov, Frank K. Wilhelm
We propose a detector of microwave photons which can distinguish the vacuum state, one-photon state, and the states with two or more photons. Its operation is based on the two-phot…
Roadmap for quantum simulation of the fractional quantum Hall effect
Michael Kaicher, Simon Balthasar Jäger, Pierre-Luc Dallaire-Demers +1
A major motivation for building a quantum computer is that it provides a tool to efficiently simulate strongly correlated quantum systems. In this work, we present a detailed roadm…
Approximating the quantum approximate optimization algorithm with digital-analog interactions
David Headley, Thorge Müller, Ana Martin +3
The quantum approximate optimisation algorithm was proposed as a heuristic method for solving combinatorial optimisation problems on near-term quantum computers and may be among th…
General solution of the time evolution of two interacting harmonic oscillators
David Edward Bruschi, G. S. Paraoanu, Ivette Fuentes +2
We study the time evolution of an ideal system composed of two harmonic oscillators coupled through a quadratic Hamiltonian with arbitrary interaction strength. We solve its dynami…
Flux Qubit Readout in the Persistent Current Basis at arbitrary Bias Points
Marius Schöndorf, Adrian Lupascu, Frank K. Wilhelm
Common flux qubit readout schemes are qubit dominated, meaning they measure in the energy eigenbasis of the qubit. For various applications meausrements in a basis different from t…
Nonpairwise interactions induced by virtual transitions in four coupled artificial atoms
M. Schöndorf, F. K. Wilhelm
The field of quantum information has matured and various protocols implementing a quantum computer are being pursued. Most similar to a classical computer is the circuit model. In…
Left-handed superlattice metamaterials for circuit QED
Anette Messinger, Bruno G. Taketani, Frank K. Wilhelm
Quantum simulations is a promising field where a controllable system is used to mimic another system of interest, whose properties one wants to investigate. One of the key issues f…
Environmental effects in quantum annealing
Tobias Chasseur, Stefan Kehrein, Frank K. Wilhelm
For quantum annealing, as opposed to circuit based quantum computing, the solution to a computational problem is encoded in the ground state of a quantum system. Therefore its susc…
Counteracting systems of diabaticities using DRAG controls: The status after 10 years
L. S. Theis, F. Motzoi, S. Machnes +1
The task of controlling a quantum system under time and bandwidth limitations is made difficult by unwanted excitations of spectrally neighboring energy levels. In this article we…
Gap-independent cooling and hybrid quantum-classical annealing
L. S. Theis, Peter K. Schuhmacher, M. Marthaler +1
In this letter we present an efficient gap-independent cooling scheme for a quantum annealer that benefits from finite temperatures. We choose a system based on superconducting flu…