Suchergebnisse

7 pags., 3 figs., 1 tab. ; Two-dimensional (2D) systems with time-dependent controls admit a quadratic Hamiltonian modeling near potential minima. Independent, dynamical normal modes facilitate inverse Hamiltonian engineering to control the system dynamics, but some systems are not separable into independent modes by a point transformation. For these "coupled systems"2D invariants may still guide the Hamiltonian design. The theory to perform the inversion and two application examples are provided: (i) We control the deflection of wave packets in transversally harmonic wave guides and (ii) we design the state transfer from one coupled oscillator to another. ; This work was supported by the Basque Country Government (Grant No. IT986-16), and by PGC2018-101355- B-I00 (MCIU/AEI/FEDER,UE). E.T. acknowledges support from PGC2018-094792-B-I00 (MCIU/AEI/FEDER,UE), CSIC Research Platform PTI-001, and CAM/FEDER No. S2018/TCS- 4342 (QUITEMAD-CM).

We consider a superconducting quantum point contact in a circuit quantum electrodynamics setup. We study three different configurations, attainable with current technology, where a quantum point contact is coupled galvanically to a coplanar waveguide resonator. Furthermore, we demonstrate that the strong and ultrastrong coupling regimes can be achieved with realistic parameters, allowing the coherent exchange between a superconducting quantum point contact and a quantized intracavity field. © 2012 American Physical Society. ; We acknowledge funding from Spanish MICINN Juan de la Cierva, FIS2009-12773-C02-01, and FIS2011-28851-C02-02; Basque Government IT472-10 and IT- 366-07; UPV/EHUUFI 11/55; SOLID, CCQED, and PROMISCE European projects. ; Peer Reviewed

Different ways to accelerate adiabatic processes in cold atom physics and atomic state preparation are reviewed. The invariant-based inverse engineering approach is applied to trap expansions and contractions, and to atomic transport. Berry's Hamiltonian is applied to produce fast versions of adiabatic passage methods. ; Se resumen distintas maneras de acelerar procesos adiabáticos en la física de átomos fríos y en la preparación de estados atómicos. Se aplica un método inverso basado en invariantes a expansiones y contracciones de trampas y al transporte atómico. También se describen versiones rápidas de los métodos de paso adiabático basadas en un Hamiltoniano propuesto por Berry. ; We are grateful to our collaborators A. Ruschhaupt, D. Guery-Odelin, S. Schmidt and A. del Campo. They have produced with us the original material reviewed here. E. T. and S. I. acknowledge financial support from the Basque Government (Grants No. BFI08.151 and BFI09.39). Funding by the Basque Government (Grant IT472-10), the Ministerio de Ciencia e Innovación (FIS2009-12773-C02-01), the National Natural Science Foundation of China (No. 60806041), the Shanghai Rising-Star Program (No. 08QA14030), the Shanghai Leading Academic Discipline (No. S30105), and Juan de la Cierva Programme is acknowledged. ; Publicado

Proceeding of: 5th International Workshop DICE2010: Space-Time-Matter-Current Issues in Quantum Mechanics and Beyond, 13–17th September 2010, Castello Pasquini, Castiglioncello, Tuscany, Italy ; We review different ways to accelerate adiabatic processes in cold atom physics and atomic state preparation. Trap expansions or contractions and atomic transport may be accelerated by an invariant-based inverse engineering approach. Berry's inverse engineering method is also applied to produce fast versions of adiabatic passage methods. ; E. T. and S. I. acknowledge financial support from the Basque Government (Grants No. BFI09.39). Funding by the Basque Government (Grant IT472-10), the Ministerio de Ciencia e Innovación (FIS2009-12773-C02-01), the National Natural Science Foundation of China (No. 60806041), the Shanghai Rising-Star Program (no. 08QA14030), the Shanghai Leading Academic Discipline (No. S30105), and Juan de la Cierva Programme is acknowledged.

7 págs., 6 figs. ; Shortcuts to adiabaticity let a system reach the results of a slow adiabatic process in a shorter time. We propose to quantify the >energy cost> of the shortcut by the energy consumption of the system enlarged by including the control device. A mechanical model where the dynamics of the system and control device can be explicitly described illustrates that a broad range of possible values for the consumption is possible, including zero (above the adiabatic energy increment) when friction is negligible and the energy given away as negative power is stored and reused by perfect regenerative braking. ; We acknowledge funding from the Basque government (Grant No. IT986-16), MINECO/FEDER, UE (Grants No. FIS2015- 67161-P and No. FIS2015-70856-P), and QUITEMAD+CM S2013-ICE2801. ; Peer Reviewed