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Oscillations and spontaneous pattern
formation are ubiquitous phenomena observed in
macroscopic dissipative non-equilibrium systems.
Examples include the formation of convection rolls
in fluids, oscillations in chemical reactions
or instabilities in lasers or gas discharge tubes.
The dynamics of all of these systems can be described
in terms of macroscopic variables obeying deterministic
rules.
Self-organization is also found in open systems
operating on the scale of several nanometers;
however, their behavior cannot be understood any
more in terms of deterministic equations. Rather,
the dynamic processes are influenced by fluctuations,
and possibly also by quantum effects. As a consequence,
nanoscale systems exhibit qualitatively new phenomena,
such as different nonlinear scenarios or scaling
behaviors. Their dynamics might thus deviate largely
from those of macroscopic non-equilibrium systems.
However, compared to macroscopic systems, the
underlying principles have not yet been established.
We investigate self-organization
at nanosized electrodes, both experimentally and
theoretically with the aim to contribute to an
understanding of the universal principles that
govern the dynamics of dissipative nanoscale systems.
We focus on electrochemical systems in far from
equilibrium situations, because, in contrast to
many other nonlinear oscillating systems, it is
feasible to experimentally investigate single
nano-oscillators as well as arrays of oscillators
and oscillatory networks. Currently, we are exploring
the impact of fluctuations on a single electrochemical
oscillator as a function of electrode size. Future
work will focus on building networks from an ensemble
of oscillators.
- V. Garcia-Morales and K. Krischer (2008).
Phys. Rev. Lett. 100, 054101.
- N. Baba, and K. Krischer (2008). Chaos
18, 015103.
- H. Varela, C. Beta, A. Bonnefont, K. Krischer
(2005). Phys. Chem. Chem. Phys. 7, 2429.
- K. Krischer (2002). In Advances in Electrochemical
Science and Engineering, edited by D. M. Kolb
and R. C. Alkire, Wiley-VCH; Vol. 8, 90ff.
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