Quantum control of chemical reactions using optimal control theory

Jianshu Cao

Anatoliy G. Butkovskiy, Yu. I. Samoilenko

K. Mishima, Koichi Yamashita

We have constructed free-time and fixed end-point optimal control theory for quantum systems and applied it to entanglement generation between rotational modes of two polar molecules coupled by dipole-dipole interaction. The motivation of the present work is to solve optimal control problems more flexibly by extending the popular fixed time and fixed end-point optimal control theory for quantum systems to free-time and fixed end-point optimal control theory. As a demonstration, the theory that we have constructed in this paper will be applied to entanglement generation in rotational modes of NaCl-NaBr polar molecular systems that are sensitive to the strength of entangling interactions. Our method will significantly be useful for the quantum control of nonlocal interaction such as entangling interaction, which depends crucially on the strength of the interaction or the distance between the two molecules, and other general quantum dynamics, chemical reactions, and so on.

Jincheng Zhang

Quantum information has emerged as a transformative tool across diverse fields, and its potential within chemical reaction rate prediction is increasingly attracting attention. This paper explores the integration of quantum information and geometric modeling to enhance the prediction of reaction rates, utilizing geometric information for optimization. We present a novel framework that leverages quantum algorithms to represent chemical reaction dynamics as geometric functions, enabling the optimization of reaction conditions based on these geometric representations. The core mechanism focuses on translating complex reaction kinetics into a simplified geometric model, allowing for efficient optimization through geometric analysis. The study demonstrates the effectiveness of this approach in predicting reaction rates, offering a promising pathway towards improved reaction control and understanding.

Fabien Gatti, Osman Atabek, Samrit Mainali

Adrien Devolder, Timur V. Tscherbul, Paul Brumer

Entanglement is a crucial resource for achieving quantum advantages in quantum computation, quantum sensing, and quantum communication. As shown in this Letter, entanglement is also a valuable resource for the coherent control of the large class of bimolecular chemical reactions. We utilize an entanglement-enhanced coherent control scheme, in which the initial preparation of the superposition state is divided into two steps: the first entangles the reactants, and the second is responsible for coherent control. This approach can overcome the limitations of traditional coherent control of scattering caused by noninterfering pathways, known as satellite terms. By tuning the amount of entanglement between reactants, the visibility of coherent control in chemical reactions can be modulated and optimized. Significantly, there exists an optimal amount of entanglement, which ensures complete indistinguishability of the reaction pathways, maximizing the extent of control. This entanglement-enhanced coherent control scheme is computationally illustrated using the ultracold KRb + KRb reaction, where perfect control over the parity of the product rotational states is achieved.