Normalized solutions for Schrödinger system with quadratic and cubic interactions
arXiv:2108.09461
Abstract
In this paper, we give a complete study on the existence and non-existence of normalized solutions for Schrödinger system with quadratic and cubic interactions. In the one dimension case, the energy functional is bounded from below on the product of -spheres, normalized ground states exist and are obtained as global minimizers. When , the energy functional is not always bounded on the product of -spheres. We give a classification of the existence and nonexistence of global minimizers. Then under suitable conditions on and , we prove the existence of normalized solutions. When , the energy functional is always unbounded on the product of -spheres. We show that under suitable conditions on and , at least two normalized solutions exist, one is a ground state and the other is an excited state. Furthermore, by refining the upper bound of the ground state energy, we provide a precise mass collapse behavior of the ground state and a precise limit behavior of the excited state as . Finally, we deal with the high dimensional cases . Several non-existence results are obtained if . When , , the system is a mass-energy double critical problem, we obtain the existence of a normalized ground state and its synchronized mass collapse behavior. Comparing with the well studied homogeneous case , our main results indicate that the quadratic interaction term not only enriches the set of solutions to the above Schrödinger system but also leads to a stabilization of the related evolution system.
59 pages