Semiclassical propagation of Wigner functions (2009)
Dittrich, Thomas, Gomez, Edgar A., Pachon, Leonardo A.
We present a comprehensive study of semiclassical phase-space propagation in the Wigner representation, emphasizing numerical applications, in particular as an initial-value representation. Two...
Time-domain scars: resolving the spectral form factor in phase space (2008)
Dittrich, Thomas, Pachon, Leonardo A.
We study the relationship of the spectral form factor with quantum as well as classical probabilities to return. Defining a quantum return probability in phase space as a trace over the propagator of...
Directed Transport in classical and quantum chaotic billiards (2008)
Acevedo, Walter, Dittrich, Thomas
We construct an autonomous chaotic Hamiltonian ratchet as a channel billiard subdivided by equidistant walls attached perpendicularly to one side of the channel, leaving an opening on the opposite...
Driven Tunneling: Chaos and Decoherence (2008)
Peter Hänggi, Sigmund Kohler, Thomas Dittrich
Abstract. Chaotic tunneling in a driven double-well system is investigated in absence as well as in the presence of dissipation. As the constitutive mechanism of chaos-assisted tunneling, we focus on...
Driven Tunneling: Chaos and Decoherence (2007)
Peter Hänggi, Sigmund Kohler, Thomas Dittrich
. Chaotic tunneling in a driven double-well system is investigated in absence as well as in the presence of dissipation. As the constitutive mechanism of chaosassisted tunneling, we focus on the...
Semiclassical propagator of the Wigner function (2005)
Dittrich, Thomas, Sandoval, Luis, Viviescas, Carlos
Propagation of the Wigner function is studied on two levels of semiclassical propagation, one based on the van-Vleck propagator, the other on phase-space path integration. Leading quantum corrections...
Wigner function for discrete phase space: exorcising ghost images (2005)
Argüelles, Arturo, Dittrich, Thomas
We construct, using simple geometrical arguments, a Wigner function defined on a discrete phase space of arbitrary integer Hilbert-space dimension that is free of redundancies. ``Ghost images''...
Directed Chaotic Transport in Hamiltonian Ratchets (2004)
Schanz, Holger, Dittrich, Thomas, Ketzmerick, Roland
We present a comprehensive account of directed transport in one-dimensional Hamiltonian systems with spatial and temporal periodicity. They can be considered as Hamiltonian ratchets in the sense that...
Classical and quantum periodically driven scattering in one dimension (2001)
Henseler, Michael, Dittrich, Thomas, Richter, Klaus
Irregular scattering at harmonically driven one- dimensional potential wells is studied both on the classical and the quantum level. We show that an ac-driven single square well, and a smooth well...
Classical and Quantum Hamiltonian Ratchets (2001)
Dittrich, Thomas, Ketzmerick, Roland, Otto, Marc-Felix, Schanz, Holger
Classical and Quantum Hamiltonian Ratchets (2000)
Schanz, Holger, Otto, Marc-Felix, Ketzmerick, Roland, Dittrich, Thomas
We explain the mechanism leading to directed chaotic transport in Hamiltonian systems with spatial and temporal periodicity. We show that a mixed phase space comprising both regular and chaotic...
Driven Tunneling: Chaos and Decoherence (1999)
Hanggi, Peter, Kohler, Sigmund, Dittrich, Thomas
Chaotic tunneling in a driven double-well system is investigated in absence as well as in the presence of dissipation. As the constitutive mechanism of chaos-assisted tunneling, we focus on the...
Kohler, Sigmund, Dittrich, Thomas, Hänggi, Peter
Using the parametrically driven harmonic oscillator as a working example, we study two different Markovian approaches to the quantum dynamics of a periodically driven system with dissipation. In the...
Spectral Statistics in Chaotic Systems with Two Identical Connected Cells (1998)
Dittrich, Thomas, Koboldt, Gert, Mehlig, Bernhard, Schanz, Holger
Chaotic systems that decompose into two cells connected only by a narrow channel exhibit characteristic deviations of their quantum spectral statistics from the canonical random-matrix ensembles. The...
Coherent and incoherent chaotic tunneling near singlet-doublet crossings (1998)
Kohler, Sigmund, Utermann, Ralf, Hanggi, Peter, Dittrich, Thomas
In the spectrum of systems showing chaos-assisted tunneling, three-state crossings are formed when a chaotic singlet intersects a tunnel doublet. We study the dissipative quantum dynamics in the...
Tunneling in a periodically driven bistable system (1991)
Fer Physik B, Frank Groflmann, Peter Jung, Thomas Dittrich
The influence of periodic driving on coherent tunneling is investigated, using a quartic double-well potential in a monochromatic external field as a working example. Extensive numerical studies of...
Dresden, Med. Akad., Diss. A, 1989 (Nicht f.d. Austausch).