Frank K. Wilhelm
Saarland University
Flux qubitSuperconducting quantum computingJosephson effectPhysicsQuantum decoherenceTopologyQuantum simulatorQuantum informationMesoscopic physicsQuantum technologyQubitCondensed matter physicsQuantum electrodynamicsOptoelectronicsQuantum error correctionSuperconductivityQuantum computerQuantum mechanicsPhase qubitQuantumOptimal control
331Publications
44H-index
7,472Citations
Publications 264
Newest
#2Symeon Chatzinotas (University of Luxembourg)H-Index: 5
#3Frank K. Wilhelm (Forschungszentrum Jülich)
We investigate the interplay between gravity and the quantum coherence present in the state of a pulse of light propagating in curved spacetime. We first introduce an operational way to distinguish between the overall shift in the pulse wavepacket and its genuine deformation after propagation. We then apply our technique to quantum states of photons that are coherent in the frequency degree of freedom, as well as to states of completely incoherent light. We focus on Gaussian profiles and frequen...
1 Citations
#1Nicolas WittlerH-Index: 2
#2Federico RoyH-Index: 4
Last. Shai MachnesH-Index: 10
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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 highly detailed system characterization required to understand the underlying error sources is an arduous process and impractical with increasing chip size. Open-loop optimal control techniques allow for the improvement of gates but are limited by the models they are based on. To rectify the situation, we provide an integra...
6 CitationsSource
Last. Andreas W. SchellH-Index: 25
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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 the dynamics analytically by employing Lie algebraic tools that allow to decouple the time-evolution operator induced by quadratic Hamiltonians. In particular, we use this result to completely chracterize the dynamics of the two oscillators interacting in the ultrastrong coupling regime. Furthermore, we compute quantities of int...
5 CitationsSource
#1Andrii M. Sokolov (Saarland University)H-Index: 1
#2Frank K. Wilhelm (Saarland University)H-Index: 44
We propose a detector of microwave photons that can distinguish the vacuum state, one-photon state, and the states with two or more photons. Its operation is based on the two-photon transition in a biased Josephson junction and detection occurs when it switches from a superconducting to a normal state. We model the detector theoretically. The detector performs with more than 90% success probability in several microseconds. The working frequency can be set at the design stage in the range from ab...
1 CitationsSource
#1Michael KaicherH-Index: 2
#2Simon B. JägerH-Index: 8
Last. Frank K. WilhelmH-Index: 44
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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 roadmap on how to simulate a two-dimensional electron gas---cooled to absolute zero and pierced by a strong transversal magnetic field---on a quantum computer. This system describes the setting of the Fractional Quantum Hall Effect (FQHE), one of the pillars of modern condensed matter theory. We give analytical expressions ...
3 CitationsSource
We show that self gravitation of a quantum system affects the quantum coherence present in its state. The system is initially prepared in a spatial superposition of two different positions of a field excitation, and we employ semiclassical gravity to find its time evolution. The coherence initially present in the state is affected when the size of the particles is much larger than their Compton length. In contrast, particles whose size is comparable or less are not affected. Furthermore, we find...
6 Citations
#1Frank K. Wilhelm (Saarland University)H-Index: 44
#2Susanna Kirchhoff (Saarland University)H-Index: 2
Last. Dominique SugnyH-Index: 31
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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 goal of demystifying its jargon. The second lecture will describe computational tools (for computations both on paper and in a computer) for its implementation as well as their conceptual background. The third chapter will go through a series of popular examples from different applications of quantum technology.
1 Citations
#1Andrii SokolovH-Index: 2
#2Frank K. WilhelmH-Index: 44
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-photon transition in a biased Josephson junction and detection occurs when it switches from a superconducting to a normal state. We model the detector theoretically. The detector performs with more than 90% success probability in several microseconds. It is sensitive for the 8.2GHz photons. The working frequency could be s...
1 CitationsSource