Spin entanglement and multiparameter spin squeezing for quantum enhanced metrology

Youssef Trifa

Istituto Nazionale di Ottica, Consiglio Nazionale delle Ricerche (INO-CNR)

Entanglement is a key resource in quantum mechanics, especially for quantum metrology as it allows to reach measurement sensitivty beyond the reach of uncorrelated, classical systems. In this talk, I will present different schemes to generate useful entanglement among large-S spin systems, focusing on the case of long-range dipolar interactions. I will discuss different forms of entanglement, and in particular (mulitparameter) spin squeezing that can be used for the common measurement of external signals. Finally, I will introduce schemes for enhanced noise reduction using a differential interferometer setup.