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Dipolar interactions are ubiquitous in nature and rule the behavior of a
broad range of systems spanning from energy transfer in biological systems to
quantum magnetism. Here, we study magnetization-conserving dipolar induced
spin-exchange dynamics in dense arrays of fermionic erbium atoms confined in a
deep three-dimensional lattice. Harnessing the special atomic properties of
erbium, we demonstrate control over the spin dynamics by tuning the dipole
orientation and changing the initial spin state within the large 20 spin

Single quantum light-emitters are valuable resources for engineered quantum
systems. They can function as robust single-photon generators, allow optical
control of single spins, provide readout capabilities for atomic-scale sensors,
and provide interfaces between stationary and flying qubits. Environmental
factors can lead to single emitters exhibiting "blinking", whereby the
fluorescence level switches between on and off states. Detailed
characterisation of this blinking behaviour including determining the switching

Vector vortex beam simultaneously carrying spin and orbital angular momentum
of light promises additional degrees of freedom for modern optics and emerging
resources for both classical and quantum information technologies. The
inherently infinite dimensions can be exploited to enhance data capacity for
sustaining the unprecedented growth in big data and internet traffic, and can
be encoded to build quantum computing machines in high-dimensional Hilbert

Entangled states with a positive partial transpose (so-called PPT states) are
central to many interesting problems in quantum theory. On one hand, they are
considered to be weakly entangled, since no pure state entanglement can be
distilled from them. On the other hand, it has been shown recently that some of
these PPT states exhibit genuinely high-dimensional entanglement, i.e. they
have a high Schmidt number. Here we investigate $d\times d$ dimensional PPT
states for $d\ge 4$ discussed recently by Sindici and Piani, and by

Correlations lie at the heart of almost all scientific predictions. It is
therefore of interest to ask whether there exist general limitations to the
amount of correlations that can be created at a finite amount of invested
energy. Within quantum thermodynamics such limitations can be derived from
first principles. In particular, it can be shown that establishing correlations
between initially uncorrelated systems in a thermal background has an energetic

In the problem of entanglement there exist two different notions. One is the
entanglement of a quantum state, characterizing the state structure. The other
is entanglement production by quantum operators, describing the action of
operators in the given Hilbert space. Entanglement production by statistical
operators, or density operators, is an important notion arising in quantum
measurements and quantum information processing. The operational meaning of the

We investigate whether entanglement can survive the thermalization of
subsystems. We present two equivalent formulations of this problem: 1. Can two
isolated agents, accessing only pre-shared randomness, locally thermalize
arbitrary input states while maintaining some entanglement? 2. Can
thermalization with local heat baths, which may be classically correlated but
do not exchange information, locally thermalize arbitrary input states while
maintaining some entanglement? We answer these questions in the positive at

Relational quantum queries are sometimes capable to effectively decide
between collections of mutually exclusive elementary cases without completely
resolving and determining those individual instances. Thereby the set of
mutually exclusive elementary cases is effectively partitioned into equivalence
classes pertinent to the respective query. In the second part of the paper, we
review recent progress in theoretical certifications (relative to the
assumptions made) of quantum value indeterminacy as a means to build quantum

We consider a general model, describing a quantum impurity with degenerate
energy levels, interacting with a gas of itinerant electrons, derive the
scaling equation and analyse the connection between its explicit form and the
symmetry of interaction. On the basis of this analysis we write down explicitly
the scaling equation for the interaction acting on $su(3)$ Lie algebra and
having either $SU(2)\times U(1)$, or $SU(2)$ symmetry.

We explore the electroluminescence efficiency for a quantum mechanical model
of a large number of molecular emitters embedded in an optical microcavity. We
characterize the circumstances under which a microcavity enhances harvesting of
triplet excitons via reverse intersystem-crossing (R-ISC) into singlet
populations that can emit light. For that end, we develop a time-local master
equation in a variationally optimized frame which allows for the exploration of

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