2.8k citations · 3.8k across the 9 of their papers we have counts for
9 papers
Reaching for the quantum limits in the simultaneous estimation of phase and phase diffusion
Magdalena Szczykulska, Tillmann Baumgratz, Animesh Datta
Phase diffusion invariably accompanies all phase estimation strategies -- quantum or classical. A precise estimation of the former can often provide valuable understanding of the p…
Efficient tomography of a quantum many-body system
B. P. Lanyon, C. Maier, M. Holzäpfel +10
Quantum state tomography (QST) is the gold standard technique for obtaining an estimate for the state of small quantum systems in the laboratory. Its application to systems with mo…
Multi-parameter Quantum Metrology
Magdalena Szczykulska, Tillmann Baumgratz, Animesh Datta
The simultaneous quantum estimation of multiple parameters can provide a better precision than estimating them individually. This is an effect that is impossible classically. We re…
Quantum enhanced estimation of a multi-dimensional field
Tillmann Baumgratz, Animesh Datta
We present a framework for the quantum enhanced estimation of multiple parameters corresponding to non-commuting unitary generators. Our formalism provides a recipe for the simulta…
Scalable reconstruction of unitary processes and Hamiltonians
M. Holzäpfel, T. Baumgratz, M. Cramer +1
Based on recently introduced efficient quantum state tomography schemes, we propose a scalable method for the tomography of unitary processes and the reconstruction of one-dimensio…
Quantifying Coherence
T. Baumgratz, M. Cramer, M. B. Plenio
We introduce a rigorous framework for the quantification of coherence and identify intuitive and easily computable measures of coherence. We achieve this by adopting the viewpoint…
A Scalable Maximum Likelihood Method for Quantum State Tomography
Tillmann Baumgratz, Alexander Nüßeler, Marcus Cramer +1
The principle of maximum likelihood reconstruction has proven to yield satisfactory results in the context of quantum state tomography for many-body systems of moderate system size…
Scalable reconstruction of density matrices
Tillmann Baumgratz, David Gross, Marcus Cramer +1
Recent contributions in the field of quantum state tomography have shown that, despite the exponential growth of Hilbert space with the number of subsystems, tomography of one-dime…
Lower Bounds for Ground States of Condensed Matter Systems
Tillmann Baumgratz, Martin B. Plenio
Standard variational methods tend to obtain upper bounds on the ground state energy of quantum many-body systems. Here we study a complementary method that determines lower bounds…