Exact transition probabilities in a six-state Landau-Zener system with path interference

TL;DR

This paper presents an exactly solvable six-state Landau-Zener model where transition probabilities can be analytically determined, revealing interference effects that challenge traditional incoherent transition assumptions.

Contribution

It introduces a new multistate Landau-Zener model with exact transition probabilities accounting for trajectory interference, expanding understanding of quantum transition systems.

Findings

Transition probabilities are exactly derived for the six-state model.

Interference effects significantly influence transition outcomes.

Numerical tests confirm the analytical expressions.

Abstract

We identify a nontrivial multistate Landau-Zener model for which transition probabilities between any pair of diabatic states can be determined analytically and exactly. In the semiclassical picture, this model features the possibility of interference of different trajectories that connect the same initial and final states. Hence, transition probabilities are generally not described by the incoherent successive application of the Landau-Zener formula. We discuss reasons for integrability of this system and provide numerical tests of the suggested expression for the transition probability matrix.