Search results for "Quantum technologie"
showing 5 items of 5 documents
Quantum state engineering using one-dimensional discrete-time quantum walks
2017
Quantum state preparation in high-dimensional systems is an essential requirement for many quantum-technology applications. The engineering of an arbitrary quantum state is, however, typically strongly dependent on the experimental platform chosen for implementation, and a general framework is still missing. Here we show that coined quantum walks on a line, which represent a framework general enough to encompass a variety of different platforms, can be used for quantum state engineering of arbitrary superpositions of the walker's sites. We achieve this goal by identifying a set of conditions that fully characterize the reachable states in the space comprising walker and coin, and providing …
Robust control for quantum technologies and quantum information processing
2022
We consider the robust inverse geometric optimization of arbitrary population transfers and single-qubit gates in a two-level system.Robustness with respect to pulse inhomogeneities is demonstrated.We show that for time or energy optimization, the pulse amplitude is constant, and we provide the analytic form of the detuning as Jacobi elliptic cosine.We deal with the task of robust complete population transfer on a 3-level quantum system in lambda configuration.First, we use the Lewis-Riesenfeld method to derive a family of solutions leading to an exact transfer.Among this family, we identify a tracking solution with a single parameter to control simultaneously the fidelity of the transfer, …
Journeys from quantum optics to quantum technology
2017
Sir Peter Knight is a pioneer in quantum optics which has now grown to an important branch of modern physics to study the foundations and applications of quantum physics. He is leading an effort to develop new technologies from quantum mechanics. In this collection of essays, we recall the time we were working with him as a postdoc or a PhD student and look at how the time with him has influenced our research.
Foundations of quantum mechanics and their impact on contemporary society
2018
Nearing a century since its inception, quantum mechanics is as lively as ever. Its signature manifestations, such as superposition, wave-particle duality, uncertainty principle, entanglement and nonlocality, were long confronted as weird predictions of an incomplete theory, paradoxes only suitable for philosophical discussions, or mere mathematical artifacts with no counterpart in the physical reality. Nevertheless, decades of progress in the experimental verification and control of quantum systems have routinely proven detractors wrong. While fundamental questions still remain wide open on the foundations and interpretations of quantum mechanics, its modern technological applications have …
Hybrid optomechanics for Quantum Technologies
2014
We review the physics of hybrid optomechanical systems consisting of a mechanical oscillator interacting with both a radiation mode and an additional matter-like system. We concentrate on the cases embodied by either a single or a multi-atom system (a Bose-Einstein condensate, in particular) and discuss a wide range of physical effects, from passive mechanical cooling to the set-up of multipartite entanglement, from optomechanical non-locality to the achievement of non-classical states of a single mechanical mode. The reviewed material showcases the viability of hybridised cavity optomechanical systems as basic building blocks for quantum communication networks and quantum state-engineering…