Our proposal for ac-driven quantum ratchets with
ultracold atoms (BEC) [23, 24] has been realized by the group of Martin Weitz [Science 326, 1241 (2009)]. They observed a whole spectrum of theoretically
predicted effects and thus demarcated their quantum ratchet from classical ones.
We have demonstrated, both theoretically (Augsburg) and experimentally (Bonn), that the mobility of a BEC in an ac-driven optical potential can be tuned by modifing the Floquet spectrum of the system.
Here you can see the results of some experiments on ac-driven quantum ratchets I have performed under the supervision of
Christopher Grossert in the Bonn lab (to be more precise, I was allowed to click the buttons).
The time-of-flight measurements reveal velocity distribution of a BEC cloud after the
exposition to an ac-driven optical lattice potential.
Current research interests
categorization of dissipative quantum chaos
It is an idea to do for dissipative (open) quantum systems what has been done for Hamiltonian quantum systems (and what is known by now as 'quantum chaos').
It is hard to describe this problem in a few words, it is rather a vision (see the outline of a recently organized topical workshop). Some steps have already been made here
applied quantum computing
Quantum computing (QC) is no longer a mere academic subject but also one of the fastest growing IT
sectors. It is a perspective job market for IT specialists, and we are already
situation when the demand for experts both in IT and computer science (CS) and QC exceeds the
Textbook quantum algorithms score low in the current context. What is needed now is
fast (at the expense of exact optimality) solutions for traffic control, image recognition, and portfolio optimization, i.e.,
solutions for practical, every-second tasks. This demands a new generation of so-called heuristic quantum
algorithms; however, they are not covered in the textbooks.
There are three of us - Sølve Selstø, Pedro Lind,
and me - who believe that the way QC is taught currently should be revised.
Our hypothesis is that IT/CS students can be led directly to the field of QC without prior knowledge of quantum mechanics.
The correspodning course should be a blend of QC theory and practial coding, by using online cloud platoforms such as
IBM Quantum Experience and D-Wave's Leap.
many-body quantum systems out of equilibrium
Many-body Floquet states of strongly-driven systems: numerical methods and algorithms [56,
Open quantum systems: asymptotic nonequilibrium states ('quantum attractors') and relaxations
towards them [ 57, 61]
On these two particular subjects, there is ongoing collaboration with the groups of
M. Ivanchenko and
I. Meyerov at
the Lobachevsky State University of Nizhny Novgorod.
We are trying to advance existing and develop new methods of compuational physics of complex
quantum system and realize them on the
Energy exchange between quantum systems and relaxation to
equilibrium [33, 35, 39].
Lévy walks, complex transport and biodynamics
Lévy walks are a specific type of random walks which
found applications in diverse research corners ranging from quantum physics and chaotic dynamics to ecology, cellular biophysics and robotics.
Currently, we are trying to apply this concept to biological transport, transport phenomena in two- and three-dimensional spaces, and optimal search theory.
On these subjects I enjoy collaboration [36,
43, 46, 50,
with V. Zaburdaev (University of Erlangen-Nuremberg, Germany) and E. Barkai (Bar-Ilan University, Israel).