Asymptotically vanishing PT-symmetric potentials and negative-mass Schroedinger equations

TL;DR

This paper explores PT-symmetric potentials with asymptotically vanishing properties and negative-mass Schrödinger equations, revealing instabilities and proposing stabilization methods in cryptohermitian quantum models.

Contribution

It introduces a novel approach to stabilize PT-symmetric Coulomb-Kratzer models using negative bare mass in Schrödinger equations.

Findings

Identification of instability in the original PT-symmetric model

Stabilization achieved through negative mass choice

Extension of PT-symmetric quantum mechanics models

Abstract

In paper I [M. Znojil and G. L\'evai, Phys. Lett. A 271 (2000) 327] we introduced the Coulomb - Kratzer bound-state problem in its cryptohermitian, PT-symmetric version. An instability of the original model is revealed and its necessary stabilization is achieved, for almost all couplings, by an unusual, negative choice of the bare mass in Schroediner equation.