Ab Initio Polaritonic Chemistry on Diverse Quantum Computing Platforms: Qubit, Qudit, and Hybrid Qubit-Qumode Architectures

arXiv (Cornell University)

Abstract

Trying to export ab initio polaritonic chemistry onto emerging quantum computers raises fundamental questions. A central one is how to efficiently represent both fermionic and bosonic degrees of freedom on the same platform, in order to develop computational strategies that can accurately capture strong electron-photon correlations at a reasonable cost for implementation on near-term hardware. Given the hybrid fermion-boson nature of polaritonic problem, one may legitimately ask: should we rely exclusively on conventional qubit-based platforms, or consider alternative computational paradigms? To explore this, we investigate in this work three strategies: qubit-based, qudit-based, and hybrid qubit-qumode approaches. For each platform, we design compact, physically motivated quantum circuit ansätze and integrate them within the state-averaged variational quantum eigensolver to compute multiple polaritonic eigenstates simultaneously. A key element of our approach is the development of compact electron-photon entangling circuits, tailored to the native capabilities and limitations of each hardware architecture. We benchmark all three strategies on a cavity-embedded H$_{2}$ molecule, reproducing characteristic phenomena such as light-induced avoided crossings. Our results show that each platform achieves comparable accuracy in predicting polaritonic eigen-energies and eigenstates. However, with respect to quantum resources required the hybrid qubit-qumode approach offers the most favorable tradeoff between resource efficiency and accuracy, followed closely by the qudit-based method. Both of which outperform the conventional qubit-based strategy. Our work presents a hardware-conscious comparison of quantum encoding strategies for polaritonic systems and highlights the potential of higher-dimensional quantum platforms to simulate complex light-matter systems.

Authors 8

1. Even Chiari

   Centre National de la Recherche Scientifique · Institut de Chimie de Strasbourg · Université de Strasbourg

   Affiliation as printed

   Laboratoire de Chimie Quantique de Strasbourg , Institut de Chimie , CNRS / Université de Strasbourg , 4 rue Blaise Pascal , 67000 Strasbourg , France

2. Wafa Makhlouf

   Centre National de la Recherche Scientifique · Institut de Chimie de Strasbourg · Université de Strasbourg

   Affiliation as printed

   Laboratoire de Chimie Quantique de Strasbourg , Institut de Chimie , CNRS / Université de Strasbourg , 4 rue Blaise Pascal , 67000 Strasbourg , France

3. Lucie Pepe

   Centre National de la Recherche Scientifique · Institut de Chimie de Strasbourg · Université de Strasbourg

   Affiliation as printed

   Laboratoire de Chimie Quantique de Strasbourg , Institut de Chimie , CNRS / Université de Strasbourg , 4 rue Blaise Pascal , 67000 Strasbourg , France

4. Emiel Koridon Aachen Instituut-Lorentz

   Leiden University · Vrije Universiteit Amsterdam

   Affiliation as printed

   Instituut-Lorentz , Universiteit Leiden , P.O. Box 9506 , 2300 RA Leiden , The Netherlands

   Theoretical Chemistry , Vrije Universiteit , De Boelelaan 1083 , NL-1081 HV , Amsterdam , The Netherlands

5. Johanna Klein

   École Nationale Supérieure de Chimie de Montpellier · Centre National de la Recherche Scientifique · Université de Montpellier · Institut Charles Gerhardt Montpellier

   Affiliation as printed

   ICGM , Univ Montpellier , CNRS , ENSCM , Montpellier , France

6. Bruno Senjean

   École Nationale Supérieure de Chimie de Montpellier · Centre National de la Recherche Scientifique · Université de Montpellier · Institut Charles Gerhardt Montpellier

   Affiliation as printed

   ICGM , Univ Montpellier , CNRS , ENSCM , Montpellier , France

7. Benjamin Lasorne

   École Nationale Supérieure de Chimie de Montpellier · Centre National de la Recherche Scientifique · Université de Montpellier · Institut Charles Gerhardt Montpellier

   Affiliation as printed

   ICGM , Univ Montpellier , CNRS , ENSCM , Montpellier , France

8. Saad Yalouz

   Centre National de la Recherche Scientifique · Institut de Chimie de Strasbourg · Université de Strasbourg

   Affiliation as printed

   Laboratoire de Chimie Quantique de Strasbourg , Institut de Chimie , CNRS / Université de Strasbourg , 4 rue Blaise Pascal , 67000 Strasbourg , France