Mohseni, MasoudRezakhani, Ali T.Aspuru-Guzik, Alan2011-01-072008Mohseni, Masoud, Ali T. Rezakhani, and Alan Aspuru-Guzik. 2008. Direct estimation of single- and two-qubit Hamiltonians and relaxation rates. Physical Review A 77(4): 042320.1050-29471094-1622http://nrs.harvard.edu/urn-3:HUL.InstRepos:4646033We provide an approach for characterization of quantum Hamiltonian systems via utilizing a single measurement device. Specifically, we demonstrate how external quantum correlations can be used for Hamiltonian identification tasks. We explicitly introduce experimental procedures for direct estimation of single- and two-qubit Hamiltonian parameters, and also for simultaneous estimation of transverse and longitudinal relaxation rates, using a single Bell-state analyzer. An advantage of our method over the earlier approaches is that it has a built-in feature which makes it suitable for partial characterization of Hamiltonian parameters.en-USJournal Article2011-01-0710.1103/PhysRevA.77.042320