A transition between energy levels at an avoided crossing is known as a Landau–Zener
transition. When a two-level system (TLS) is subject to periodic driving with sufficiently large …

Quantum metrology is one of the most promising applications of quantum technologies. The
aim of this research field is the estimation of unknown parameters exploiting quantum …

We review the physical phenomena that arise when quantum mechanical energy levels are
modulated in time. The dynamics resulting from changes in the transition frequency is a …

We show that quantum Fisher information provides a sufficient condition to recognize
multiparticle entanglement in an N qubit state. The same criterion gives a necessary and …

Entanglement is the key quantum resource for improving measurement sensitivity beyond
classical limits. However, the production of entanglement in mesoscopic atomic systems has …

On-chip integrated photonic circuits are crucial to further progress towards quantum
technologies and in the science of quantum optics. Here we report precise control of single …

The modern scientific method is critically dependent on precision measurements of physical
parameters. A classic example is the measurement of the optical phase enabled by optical …

We show that the phase sensitivity Δ θ of a Mach-Zehnder interferometer illuminated by a
coherent state in one input port and a squeezed-vacuum state in the other port is (i) …

An SU (1, 1) interferometer, which replaces the beam splitters in a Mach–Zehnder
interferometer with nonlinear interactions, offers the potential of achieving improved phase …

We study the effect of losses on the phase sensitivity of the SU (1, 1) interferometer for
different configurations. We find that this type of interferometer is robust against losses that …