Hamiltonian tomography: the quantum (system) measurement problem

Abstract

To harness the power of controllable quantum systems for information processing or quantum simulation, it is essential to be able to accurately characterise the system's Hamiltonian. Although in principle this requires determining less parameters than full quantum process tomography, a general and extendable method for reconstructing a general Hamiltonian has been elusive. In their recent paper, Wang et al (2015 New J. Phys. http://dx.doi.org/10.1088/1367-2630/17/9/093017 17 http://dx.doi.org/10.1088/1367-2630/17/9/093017 ) apply dynamical decoupling to the problem of Hamiltonian tomography and show how to reconstruct a general many-body Hamiltonian comprised of arbitrary interactions between qubits.

Keywords

• Hamiltonian tomography
• system identification
• Hamiltonian characterisation