When a magnetic impurity exists in a metal, conduction electrons form a spin cloud that
screens the impurity spin. This basic phenomenon is called the Kondo effect,. Unlike electric …

Impurities or boundaries often impose nontrivial boundary conditions on a gapless bulk,
resulting in distinct boundary universality classes for a given bulk, phase transitions, and …

Magnetic impurities embedded in a metal are screened by the Kondo effect, signaled by the
formation of an extended correlation cloud, the so-called Kondo or screening cloud. In a …

Quantum entanglement between an impurity and its environment is expected to be central in
quantum impurity problems. We develop a method to compute the entanglement in spin-1/2 …

In the previous part, it was discussed that despite the apparent simplicity of quantum impurity
models, they hide non trivial physics and their solution is in general a hard task. Indeed, the …

We propose a variational approach for computing the macroscopic entanglement in a many-
body mixed state, based on entanglement witness operators, and compute the …

We study the nonequilibrium formation of a spin screening cloud that accompanies the
quenching of a local magnetic moment immersed in a Fermi sea at zero temperature. Based …

We investigate the entanglement properties of a standard circuit-QED setup that consists of
a Cooper pair box coupled to a long chain of Josephson junctions. We calculate the static …

We present a completely unbiased and controlled numerical method to solve quantum
impurity problems in d-dimensional lattices. This approach is based on a canonical …

Quantum entanglement between an impurity spin and electrons nearby is a key property of
the single-channel Kondo effects. We show that the entanglement can be detected by …