Quantum simulation of spin entanglement in QCD strings using a Kondo-type Hamiltonian

by Wenjie Gong (Harvard University)

Monday 18 Oct 2021, 14:00 → 16:00 US/Eastern

Experiments at high-energy colliders have probed the internal structure of nucleons, yielding information regarding the momentum and spin of their quark and gluon constituents. However, much remains unknown regarding the dynamics of the partons within nuclear matter, including their interactions prior to hadronization. Quantum computers, which capitalize upon the evolution of quantum ensembles to perform computational tasks, provide an attractive platform for simulating the quantum many-body interactions of partons before fragmentation. Here, we quantum simulate the dynamical evolution of spin correlations within strings of partons. We model these quantum chromodynamics (QCD) strings by letting strange quarks act as effective spin impurities mediated by lighter (up and down) quark matter. The evolution of entanglement between the spin impurities is examined using a modified version of the Kondo Lattice Model at half-filling, derived with applicability to universal digital quantum computing platforms. Entanglement between a pair of spins is assessed using two-particle correlations and the partial positive transpose (PPT) criterion of entanglement. Numerical simulations show that spin entanglement between strange particles in a QCD string oscillates coherently at antiferromagnetic coupling, indicating the possibility of parton entanglement persisting after hadronization.