Quantum Processor Calculates Ground State Energy of Helium Molecule with High Accuracy Using VQE

On April 10, 2025, researchers Badie Ghavami and Forouzan Mirmasoudi introduced a novel approach utilizing a four-qubit photonic processor with the Variational Quantum Eigensolver (VQE) to determine helium’s ground state energy, achieving higher accuracy than classical computational methods.

The study demonstrates the application of the Variational Eigensolver (VQE) algorithm on a four-qubit quantum processor to calculate the ground state energy of the Helium molecule. The results achieved higher accuracy than classical methods such as Hartree-Fock and density functional theory, highlighting the potential of quantum algorithms for solving many-body problems in chemistry and materials science. This work underscores the advantages of quantum processors in simulating molecular properties with high precision, paving the way for future applications in more complex systems.

Quantum computing has long been recognized as a transformative technology, with the potential to solve complex problems that classical computers find intractable. Recent progress in programmable nanophotonic chips has brought this vision closer to reality, particularly through their application in quantum simulations and boson sampling—a critical benchmark for demonstrating quantum supremacy. This article examines the latest developments in photonic chip-based quantum computing, exploring the methodology, key findings, and broader implications of this research.

At the core of these advancements lies the programmable nanophotonic chip, a device that manipulates photons—particles of light—to perform quantum computations. Unlike traditional approaches such as trapped ions or superconducting circuits, photonic chips offer distinct advantages, including scalability and lower error rates.

The process involves encoding quantum information into photons and routing them through an intricate network of optical pathways on the chip. By precisely controlling photon interactions, researchers can simulate complex quantum systems that are computationally intensive for classical computers. This capability is particularly valuable for tasks like boson sampling, which tests whether a quantum system can outperform its classical counterpart.

Experiments using photonic chips have successfully achieved boson sampling, producing results that would be prohibitively time-consuming for even the most advanced supercomputers. This milestone highlights the potential of quantum computing to revolutionize fields such as cryptography, optimization, and materials science.

One notable achievement is the ability to scale up the number of photons used in these experiments. As the complexity of the system increases, so does the computational burden on classical systems, making photonic chips an attractive option for future quantum applications. Additionally, the programmability of these devices allows researchers to reconfigure them for different tasks, enhancing their versatility and practicality.

The success of photonic chip-based quantum simulations has significant implications for both academia and industry. For researchers, this technology provides a powerful tool for exploring fundamental quantum mechanics and testing new algorithms. For businesses, it opens doors to solving optimization problems—such as supply chain management or drug discovery—with unprecedented efficiency.

Moreover, the scalability of photonic chips suggests they could play a pivotal role in building large-scale quantum computers. While challenges remain, such as maintaining coherence and reducing noise, the progress made so far is encouraging. As the technology evolves, it is likely to become an integral part of the quantum computing landscape.

The development of programmable nanophotonic chips represents a significant step forward in quantum computing. By enabling advanced simulations and achieving milestones like boson sampling, these devices demonstrate the potential to transform industries and solve problems that were previously intractable. As research continues, photonic chips are poised to play a central role in unlocking the full capabilities of quantum technology.