Scalable quantum computing with highly magnetic atoms

Sara Campbell

Seonggil Lee

The generalized Quantum Rabi Model (QRM), when interpreted as a bipartite magnetic graph, reveals the deep structural topology of atom-light interactions. This paper elevates the Magnetic Graph Quantum Dynamics (MGQD) framework by fusing it with Rough Operator Algebra (ROA) and Seonggil Matrix Theory (SMT). By mapping the NP-hard subgraph disconnection cost C(η) to the polynomial-time invariant eigenvalue λ_max(S_M) and redefining quantum measurement as a Sashangmugak dimensional collapse at the Seonggil Critical Horizon, we establish a fully unified computational operating system for superposition, entanglement, compiling, and error mitigation in scalable quantum hardware.

Petar Bojović, Timon Hilker, Si Wang +7 more

Abstract Quantum simulations of electronic structure and strongly correlated quantum phases are among the most promising applications of quantum computing. These computations benefit from native fermionic encodings 1,2 , enforcing fermionic statistics and conservation laws such as particle number and magnetization 3 independent of gate errors. While ultracold atoms in optical lattices have become established as powerful analogue simulators of strongly correlated fermionic matter 4–7 , neutral-atom platforms have concurrently emerged as versatile, scalable architectures for spin-based digital quantum computation 8 . Unifying these capabilities requires high-fidelity motionally coherent gates for fermionic atoms 9–11 , similar to collisional gates in bosonic systems 12,13 , paving the way for programmable fermionic quantum processors. Here we demonstrate collisional entangling gates with fidelities up to 99.75(6)% and Bell-state lifetimes exceeding 10 s, realized by means of controlled interactions of fermionic atoms in an optical superlattice. Using quantum gas microscopy 14 , we microscopically characterize spin-exchange and pair-tunnelling gates and realize a robust composite pair-exchange gate, a key building block for quantum chemistry simulations 3,15 . Our results establish controlled collisions in optical lattices as a competitive and complementary route to high entangling gate fidelities in neutral-atom quantum computers. Operating intrinsically with fermions, this capability naturally extends to many-qubit architectures, in which fermionic statistics become relevant, enabling complex state preparation and advanced readout 16–19 in scalable analogue–digital hybrid quantum simulators. Combined with local addressing 20,21 , these gates mark a crucial step towards a fully digital fermionic quantum computer based on controlled motion and entanglement of neutral atoms.

Paola Cappellaro

Benjamin N Goodberry

Vittorio Giovannetti, P. Tombesi, David Vitali

We propose a scheme for quantum computing using high-Q cavities. In this scalable scheme, the qubits are represented by single-cavity modes restricted in the space spanned by the two lowest Fock states 0) and 1). One and two-qubit operations are performed via atoms sequentially crossing the cavities.