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Electrically-active defects have a significant impact on the performance of
electronic devices based on wide band-gap materials such as diamond. This issue
is ubiquitous in diamond science and technology, since the presence of charge
traps in the active regions of different classes of diamond-based devices
(detectors, power diodes, transistors) can significantly affect their
performances, due to the formation of space charge, memory effects and the
degradation of the electronic response associated with radiation damage. Among

Thermally stable quantum states with multipartite entanglements led by
frustration are found in the antiferromagnetic spin-1/2 Heisenberg hexagon. The
model has been solved exactly to obtain all analytic expressions of eigenvalues
and eigenfunctions. Detection and characterizations for various types of
entanglements have been carried out in terms of concurrence and entanglement
witnesses based on several thermodynamic observables. Variations of
entanglement properties with respect to temperature and frustration are

Classical mechanics, relativity, electrodynamics and quantum mechanics are
often depicted as separate realms of physics, each with its own formalism and
notion. This remains unsatisfactory with respect to the unity of nature and to
the necessary number of postulates. We uncover the intrinsic connection of
these areas of physics and describe them using a common symplectic Hamiltonian
formalism. Our approach is based on a proper distinction between variables and

We describe how to introduce dynamics for the holographic states and codes
introduced by Pastawski, Yoshida, Harlow and Preskill. This task requires the
definition of a continuous limit of the kinematical Hilbert space of a finite H
which we argue may be achieved via the semicontinuous limit of Jones. Dynamics
is then introduced by building a unitary representation of a group known as
Thompson's group T, which is closely related to the conformal group

A permutation-invariant quantum code on $N$ qudits is any subspace stabilized
by the matrix representation of the symmetric group $S_N$ as permutation
matrices that permute the underlying $N$ subsystems. When each subsystem is a
complex Euclidean space of dimension $q \ge 2$, any permutation-invariant code
is a subspace of the symmetric subspace of $(\mathbb C^q)^N.$ We give an
algebraic construction of new families of of $d$-dimensional
permutation-invariant codes on at least $(2t+1)^2(d-1)$ qudits that can also

For certain correlated electron-photon systems we construct the exact
density-to-potential maps, which are the basic ingredients of a
density-functional reformulation of coupled matter-photon problems. We do so
for numerically exactly solvable models consisting of up to four fermionic
sites coupled to a single photon mode. We show that the recently introduced
concept of the intra-system steepening (T.Dimitrov et al., 18, 083004 NJP
(2016)) can be generalized to coupled fermion-boson systems and that the

Theoretical achievements, as well as much controversy, surround multiverse
theory. Various types of multiverses, with an increasing amount of complexity,
were suggested and thoroughly discussed by now. While these types are very
different, they all share the same basic idea - our physical reality consists
of more than just one universe. Each universe within a possibly huge multiverse
might be slightly or even very different from the others. The quilted
multiverse is one of these types, whose uniqueness arises from the postulate

The quantum Zeno effect is the suppression of Hamiltonian evolution by
repeated observation, resulting in the pinning of the state to an eigenstate of
the measurement observable. Using measurement only, control of the state can be
achieved if the observable is slowly varied such that the state tracks the now
time-dependent eigenstate. We demonstrate this using a circuit-QED readout
technique that couples to a dynamically controllable observable of a qubit.

On the path towards quantum gravity, we find friction between temporal
relations in quantum mechanics (QM) (where they are fixed and
field-independent), and in general relativity (where they are field-dependent
and dynamic). This paper aims to attenuate that friction, by encoding gravity
in the timeless configuration space of spatial fields with dynamics given by a
path integral. The framework demands that boundary conditions for this path
integral be uniquely given, but unlike other approaches where they are

Minimal length of a two-dimensional Klein-Gordon oscillator is investigated
and illustrates the wave functions in the momentum space. The energy
eigenvalues are found and the corresponding wave functions are calculated in
terms of hyper-geometric functions.