# ${L^p}$-theory for Schr\"odinger systems

## TL;DR

This paper develops an $L^p$-theory for vector-valued Schr"odinger operators, proving generation of contraction semigroups and analyzing their properties using advanced operator theory techniques.

## Contribution

It introduces a novel $L^p$-framework for Schr"odinger systems and applies a noncommutative Dore-Venni theorem to establish semigroup generation.

## Key findings

- Generated strongly continuous contraction semigroups on $L^p$ spaces.
- Proved semigroup extension to $L^1$, positivity, and ultracontractivity.
- Showed the generator has a compact resolvent.

## Abstract

In this article we study for $p\in (1,\infty)$ the $L^p$-realization of the vector-valued Schr\"odinger operator $\mathcal{L}u := \mathrm{div} (Q\nabla u) + V u$. Using a noncommutative version of the Dore-Venni theorem due to Monniaux and Pr\"uss, we prove that the $L^p$-realization of $\mathcal{L}$, defined on the intersection of the natural domains of the differential and multiplication operators which form $\mathcal{L}$, generates a strongly continuous contraction semigroup on $L^p(\mathbb{R}^d; \mathbb{R}^m)$. We also study additional properties of the semigroup such as extension to $L^1$, positivity, ultracontractivity and prove that the generator has compact resolvent.