Quantum information for quantum parameter estimation - Michail Skoteiniotis

Parameter estimation is a pivotal task both in science and engineering. It has been known for quite some time that the use of distinctively quantum features can boost the precision of estimation of parameters, such as optical phase, frequency, magnetic fields etc, beyond that achievable by classical means. In recent years techniques from quantum information theory, both theoretical as well as experimental, have allowed us to establish rigorous lower bounds on the estimation precision, as well as explicit strategies on how to achieve these bounds. In this talk I will give a detailed description of how techniques from quantum information—in particular the use of quantum error-correcting codes and quantum control—can help boost the precision with which pertinent parameters can be estimated in the presence of general noise models. In addition, I will show how the ultimate precision limits allowed in nature, even if we assume a theory more powerful than quantum mechanics, can be determined by a single physical principle; that of no superluminal signalling.