Berlin 2014 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

Q: Fachverband Quantenoptik und Photonik

Q 43: Quantum information: Concepts and methods II

Q 43.2: Talk

Thursday, March 20, 2014, 14:30–14:45, Kinosaal

Optimal coherent control to counteract dissipation — •Clemens Gneiting, Simeon Sauer, and Andreas Buchleitner — Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg

Genuine quantum features such as entanglement or coherence are resources as precious as fragile, and their uncovering usually requires strong efforts in isolating and controlling quantum systems. While there has been unprecedented progress in the quantum control of various model systems, e.g. trapped ions, quantum dots, or cold atoms, it is impossible to fully suppress the detrimental effect of decoherence. Standard optimal control techniques therefore focus on accessing quantum features in a finite, generically short time window. We investigate to what extent coherent Hamiltonian control can enduringly counteract the detrimental effect of decoherence. Explicitly, we determine Hamiltonians that optimally stabilize given control objectives in the presence of dissipation. Our method is applicable to both static and periodically time-dependent Hamiltonians. To demonstrate this, we discuss the maximum asymptotic two-qubit entanglement that can be preserved by static and periodic coherent control in the presence of a dissipation-inducing environment.
[1] Simeon Sauer, Clemens Gneiting, and Andreas Buchleitner, Phys. Rev. Lett. 111, 030405 (2013)