Practical Quantum State Tomography for Gibbs states

TYPEQuantum Information Seminar
Speaker:Yotam Lifshitz
Organizer:Itai Arad
Time:14:30 - 15:30
Location:Lidow Nathan Rosen (300)
Quantum state tomography is an essential tool for the characterization and verification of quantum states. However, as it cannot be directly applied to systems with more than a few qubits, efficient tomography of larger states on mid-sized quantum devices remains an important challenge. 
I will present Hamiltonian Learning Tomography, a novel tomography approach we developed. It requires moderate computational and quantum resources for the tomography of states that can be approximated by Gibbs states of local Hamiltonians. The proposed method uses a Hamiltonian learning algorithm to get a parametrized ansatz for the Gibbs Hamiltonian and optimizes it with respect to the results of local measurements. 
We demonstrated the utility of this method with a high-fidelity reconstruction of the density matrix of 4 to 10 qubits in a Gibbs state of the transverse-field Ising model, in numerical simulations as well as in experiments on IBM Quantum superconducting devices.
The talk will be in hybrid format.
People are encouraged to be present physically.