Minimal Environments

In this talk, I will discuss some aspects of the interaction of simple quantum systems with environments having a small number of degrees of freedom. I will consider two models of coupled quantum systems affected by minimal noisy environments: i) a two-qubit system in contact with a single-mode field, and ii) a qubit-field system in contact with a single qubit. I will address the dynamics of quantities such as the quantum state purity and quantum coherence of the systems of interest, as well as in which way those properties depend on the features of the small environments. The above-mentioned models admit non-perturbative analytical solutions, allowing the use of a wide range of values of coupling constants. The study of the influence of environments with a size comparable to the quantum systems of interest may be relevant to the development of quantum technologies.