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arXiv · 1508.01550

The random Schr\"odinger equation: slowly decorrelating time-dependent potentials

Yu Gu·Lenya Ryzhik
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Abstract

We analyze the weak-coupling limit of the random Schr\"odinger equation with low frequency initial data and a slowly decorrelating random potential. For the probing signal with a sufficiently long wavelength, we prove a homogenization result, that is, the properly compensated wave field admits a deterministic limit in the "very low" frequency regime. The limit is "anomalous" in the sense that the solution behaves as $\exp(-Dt^{s})$ with $s>1$ rather than the "usual"~$\exp(-Dt)$ homogenized behavior when the random potential is rapidly decorrelating. Unlike in rapidly decorrelating potentials, as we decrease the wavelength of the probing signal, stochasticity appears in the asymptotic limit -- there exists a critical scale depending on the random potential which separates the deterministic and stochastic regimes.

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Yu Gu, Lenya Ryzhik. 2015-08-06. The random Schr\"odinger equation: slowly decorrelating time-dependent potentials. https://arxiv.org/abs/1508.01550

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