Quantum Nonadiabatic Cloning of Entangled Coherent States

TL;DR

This paper introduces a systematic basis set extension method for nonadiabatic quantum dynamics of entangled nuclear coherent states, enhancing the accuracy of simulations by cloning basis functions based on generalized forces.

Contribution

It presents a novel cloning approach for basis functions in nonadiabatic dynamics, improving the representation of entangled states within the TDVP framework.

Findings

Cloning basis functions extends the basis set dynamically.

Generalized forces effectively determine cloning moments.

Method improves quantum dynamics simulations of entangled states.

Abstract

We propose a systematic approach to the basis set extension for nonadiabatic dynamics of entangled combination of nuclear coherent states (CSs) evolving according to the time-dependent variational principle (TDVP). TDVP provides a rigorous framework for fully quantum nonadiabatic dynamics of closed systems, however, quality of results strongly depends on available basis functions. Starting with a single nuclear CS replicated vertically on all electronic states, our approach clones this function when replicas of the CS on different electronic states experience increasingly different forces. Created clones move away from each other (decohere) extending the basis set. To determine a moment for cloning we introduce generalized forces based on derivatives that maximally contribute to a variation of the total quantum action and thus account for entanglement of all basis functions.