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We describe a many-body theory for interlayer dispersion forces between
weakly disordered atomically-thin crystals and numerically investigate the role
of disorder for different layer-separation distances and for different
densities of optically-induced electrons and holes. In contrast to the common
wisdom that disorder tends to enhance the importance of Coulomb interactions in
Fermi liquids, we find that short-range disorder tends to weaken interlayer
dispersion forces. We demonstrate that disorder alters the scaling laws of

In the rapidly growing area of quantum information, the Deutsch algorithm is
ubiquitous and, in most cases, the first one to be introduced to any student of
this relatively new field of research. The reason for this historical relevance
stems from the fact that, although extremely simple, the algorithm conveys all
the main features of more complex quantum computations. In spite of its
simplicity, the uncountable experimental realizations of the algorithm in a

The electronic Hong-Ou-Mandel interferometer in the integer quantum Hall
regime is an ideal system to probe the building up of quantum correlations
between charge carriers and it has been proposed as a viable platform for
quantum computing gates. Using a parallel implementation of the split-step
Fourier method, we simulated the antibunching of two interacting fermionic wave
packets impinging on a quantum point contact. Numerical results of the exact
approach are compared with a simplified theoretical model based on

We show that an array of qubits embedded in a waveguide can emit entangled
pairs of microwave photon beams. The quadratures obtained from a homodyne
detection of these outputs beams form a pair of correlated continuous variables
similarly to the EPR experiment. The photon pairs are produced by the decay of
plasmon-like collective excitations in the qubit array. The maximum intensity
of the resulting beams is only bounded by the number of emitters. We calculate

Quantum steering is a notion introduced by Schr\"odinger in order to capture
the essence of the Einstein-Podolsky-Rosen argument. In this paper we review
the theory of quantum steering. We present the basic definitions of steering
and local hidden state models and their relation to entanglement and Bell
nonlocality. Then, we describe the various criteria to characterize
steerability and structural results on the phenomenon. A detailed discussion is
given on the connections between steering and incompatibility of quantum

A Bell experiment can be conceptualized as a box, i.e., a process taking
classical setting variables to classical outcome variables, which has a
common-cause structure, i.e., one that can be realized by implementing local
measurements on systems that are prepared by a common-cause mechanism, with no
cause-effect relations across the wings of the experiment. For such
common-cause boxes, one can define a distinction between classical and
nonclassical in terms of what type of causal model (classical or nonclassical)

We introduce a new information theoretic measure of quantum correlations for
multiparticle systems. We use a form of multivariate mutual information -- the
interaction information and generalize it to multiparticle quantum systems.
There are a number of different possible generalizations. We consider two of
them. One of them is related to the notion of quantum discord and the other to
the concept of quantum dissension. This new measure, called dissension vector,

Quantum states, no matter pure states, density matrices or Wigner functions,
fully describe a physical system at a particular time. Time remains to be one
of the deepest mysteries in physics for centuries. Here we attempt to
understand time via a unified approach on both space and time, under the
intuition that relativity treats space and time on an equal footing; thus we
build quantum states across spacetime instead of only on spatial slices. We no
longer distinguish measurements on the same system at different times with

Quantum states for bipartite composite systems are categorised as either
separable or entangled, but the states can also be divided differently into
Bell local or Bell non-local states. This paper presents a detailed
classification of quantum states for bipartite systems and describes the
interrelationships between the various types. For the Bell local states there
are three cases depending on whether both, one of or neither of the local
hidden variable theory probabilities for each sub-system are also given by a

We propose a brand-new formulation of capacitated vehicle routing problem
(CVRP) as quadratic unconstrained binary optimization (QUBO). The formulated
CVRP is equipped with time-table which describes time-evolution of each
vehicle. Therefore, various constraints associated with time are successfully
realized. With a similar method, constraints of capacities are also introduced,
where capacitated quantities are allowed to increase and decrease according to
the cities which vehicles arrive. As a bonus of capacity-qubits, one also