[Hybrid RBRC seminar] Enhancing quantum utility: simulating large-scale quantum spin chains on superconducting quantum computers

by Talal Chowdhury (Kansas University)

Thursday 11 Jan 2024, 12:30 → 13:30 US/Eastern

2-160 (https://bnl.zoomgov.com/j/1619458475?pwd=Z1VDdXVXcWF1eUhsRDZObVJnME4rUT09)

We present the quantum simulation of the frustrated quantum spin-$\frac{1}{2}$ antiferromagnetic Heisenberg spin chain with competing nearest-neighbor and next-nearest-neighbor exchange interactions in the real superconducting quantum computer with qubits ranging up to 100. In particular, we implement, for the first time, the Hamiltonian with the next-nearest neighbor exchange interaction on IBM's superconducting quantum computer and carry out the time evolution of the spin chain by employing first-order Trotterization. Furthermore, our novel implementation of second-order Trotterization for the isotropic Heisenberg spin chain, involving only nearest-neighbor exchange interaction, enables precise measurement of the expectation values of staggered magnetization observable across a range of up to 100 qubits. Our demonstration of the accurate measurement of expectation values for the large-scale quantum system using superconducting quantum computers designates the quantum utility of these devices for investigating various properties of many-body quantum systems. This will be a stepping stone to achieving the quantum advantage over classical ones in simulating quantum systems before the fault tolerance quantum era.