Fisher information and quantum systems with position-dependent effective mass

We show that effective masses in nonrelativistic quantum mechanics arise in a natural fashion from the Frieden and Soffer's Principle of Extremal Info rmation (EPI) when the mean values of operators involving the momentum (p) over cap and exhibiting the form (p) over cap f((x) over cap)(p) over cap a re included as constraints. A position-dependent effective mass, which is c urrently used in the literature as a simple model for diverse phenomena in quantum physics, appears after extremalizing Fisher's information measure w ith the above constraints. (C) 2000 Elsevier Science B.V. All rights reserv ed.