Quenched asymptotics for symmetric L\'evy processes
interacting with Poissonian fields
Abstract:
We establish the quenched large time asymptotics for the Feynman-Kac
functional
\[E_x\left[\exp\left(-\int_0^tV^w(Z_s)\,ds\right)\right]\]
associated with a
pure-jump symmetric Lévy process \((Z_t)_{t\ge0}\) in general Poissonian
random potentials \(V^w\) on \(R^d\), which is closely related to the
large time asymptotic behavior of solutions to the nonlocal parabolic
Anderson problem with Poissonian interaction. In particular, when the
density function with respect to the Lebesgue measure of the associated
Lévy measure is given by \[\rho(z)=
\frac{1}{|z|^{d+\alpha}}I_{\{|z|\le 1\}}+ e^{-c|z|^\theta}I_{\{|z|>
1\}}\] for some \(\alpha\in (0,2)\), \(\theta\in (0,\infty]\) and \(c>0\), an explicit quenched asymptotics
is derived for potentials with the shape function given by \(\varphi(x)=1\wedge |x|^{-d-\beta}\) for
\(\beta\in (0,\infty]\) with \(\beta\neq 2\), and it is completely
different for \(\beta>2\) and \(\beta<2\). We also discuss the quenched
asymptotics in the critical case (e.g.,  \(\beta=2\) in the example above). The work
fills the gaps of the related work for pure-jump symmetric Lévy
processes in Poissonian potentials, where only the case that the shape
function is compactly supported (e.g., \(\beta=\infty\) in the example above) has
been handled in the literature.
2010 AMS Mathematics Subject Classification: Primary 60G52;
Secondary 60J25, 60J55, 60J35, 60J75.
Keywords and phrases: symmetric Lévy process, Poissonian potential,
quenched asymptotic,
nonlocal parabolic Anderson problem, spectral theory.