• Corpus ID: 253238063

Quantum Systems at The Brink

  title={Quantum Systems at The Brink},
  author={Dirk Hundertmark and Michal Jex and Markus Lange},
We present a method to calculate the asymptotic behavior of eigenfunctions of Schrödinger operators that also works at the threshold of the essential spectrum. It can be viewed as a higher order correction to the well-known WKB method which does need a safety distance to the essential spectrum. We illustrate its usefulness on examples of quantum particles in a potential well with a long-range repulsive term outside the well. 

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