First-Passage Kinetic Monte Carlo method

• We present a new effcient method for Monte Carlo simulations of diusion-reaction processes. First introduced by us in [Phys. Rev. Lett., 97:230602, 2006], the new algorithm skips the traditionalsmall diusion hops and propagates the diusing particles over long distances through asequence of super-hops, one particle at a time. By partitioning the simulation space into nonoverlappingprotecting domains each containing only one or two particles, the algorithm factorizesthe N-body problem of collisions among multiple Brownian particles into a set of much simplersingle-body and two-body problems. Ecient propagation of particles inside their protective domainsis enabled through the use of time-dependent Green's functions (propagators) obtained assolutions for the rst-passage statistics of random walks. The resulting Monte Carlo algorithmis event-driven and asynchronous; each Brownian particle propagates inside its own protectivedomain and on its own time clock. The algorithm reproduces the statistics of the underlyingMonte-Carlo model exactly. Extensive numerical examples demonstrate that for an importantclass of diusion-reaction models the new algorithm is effcient at low particle densities, whereother existing algorithms slow down severely.

Subject headings

NATURVETENSKAP  -- Fysik -- Den kondenserade materiens fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Condensed Matter Physics (hsv//eng)

Keyword

Brownian motion; Green's function methods; Monte Carlo methods; N-body problems; reaction-diffusion systems

Defects and diffusion

Defekter och diffusion

Publication and Content Type

ref (subject category)

art (subject category)