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We show that it is possible to construct a preparation non-contextual
ontological model that does not exhibit "transformation contextuality" for
single qubits in the stabilizer subtheory. In particular, we consider the
"blowtorch" map and show that it does not exhibit transformation contextuality
under the Grassmann Wigner-Weyl-Moyal (WWM) qubit formalism. Furthermore, the
transformation in this formalism can be fully expressed at order $\hbar^0$ and
so does not qualify as a candidate quantum phenomenon. In particular, we find

Thermodynamic properties of Robin quantum well with extrapolation length
$\Lambda$ are analyzed theoretically both for canonical and two grand canonical
ensembles with special attention being paid to situation when energies of one
or two lowest-lying states are split-off from rest of spectrum by large gap
that is controlled by varying $\Lambda$. For single split-off level, which
exists for the geometry with equal magnitudes but opposite signs of Robin
distances on confining interfaces, heat capacity $c_V$ of canonical averaging

The interplay between exctions and vibrations is considered to be a key
factor in determining the exciton transfer properties in light-harvesting
exciton transfer complexes. Here we study this interplay theoretically in a
model for exciton transport, composed of two chromophores coupled to an exciton
source and sink in the presence of vibrations. We consider two cases, that show
qualitatively distinct transport features. In the first, the vibrations are

Shannon quantum information entropies $S_{x,k}$, Fisher informations
$I_{x,k}$, Onicescu energies $O_{x,k}$ and statistical complexities
$e^{S_{x,k}}O_{x,k}$ are calculated both in the position (subscript $x$) and
momentum ($k$) representations for the Robin quantum well characterized by the
extrapolation lengths $\Lambda_-$ and $\Lambda_+$ at the two confining
surfaces. The analysis concentrates on finding and explaining the most
characteristic features of these quantum information measures in the whole

A simple and natural introduction to the concept and formalism of spontaneous
wave function collapse can and should be based on textbook knowledge of
standard quantum state collapse and monitoring. This approach explains the
origin of noise driving the paradigmatic stochastic Schr\"odinger equations of
spontaneous localization of the wave function $\Psi$. It reveals, on the other
hand, that these equations are empirically redundant and the master equations
of the noise-averaged state $\hat\rho$ are the only empirically testable

Resource theories are a generic approach used to manage any valuable
resource, such as entanglement, purity, and asymmetry. Such frameworks are
characterized by two main elements: a set of predefined (free) operations and
states, that one assumes to be easily obtained at no cost. Given these ground
rules, one can ask: what is achievable by using such free operations and
states? This usually results in a set of state transition conditions, that tell
us if a particular state $ \rho $ may evolve into another state $ \rho' $ via

We propose and demonstrate using a quantum sensor based on thermal Rydberg
atoms to perform a non-destructive measurement of electric fields in the
extreme electrically small regime, with a sensing volume over $10^7$ times
smaller than the cube of the electric field wavelength. We introduce the
standard quantum limit for data capacity, and experimentally observe
quantum-limited data reception for bandwidths from 10~kHz up to 30~MHz. In
doing this, we provide a useful alternative to classical communication

Hawking's black hole evaporation process has led to several paradoxes,
stimulating searches for new physics. Without introducing any exotic objects,
we here show that in fact after the full black hole evaporation the outgoing
Hawking particles are entangled with each other and are consequently in a pure
state. At any stage of the evaporation process, we carefully track the
entanglement of the state of matter and Hawking particles. However, in the case
of full evaporation, we show that the entanglement is transferred from

Using the quantum transition path time probability distribution we show that
time averaging of weak values leads to unexpected results. We prove a weak
value time energy uncertainty principle and time energy commutation relation.
We also find that time averaging allows one to predict in advance the momentum
of a particle at a post selected point in space with accuracy greater than the
limit of $\hbar /2$ as dictated by the uncertainty principle. This comes at a

We investigate spontaneous and pumped entanglement of two level systems in
the vicinity of a photonic topological insulator interface, which supports a
nonreciprocal (unidirectional), scattering-immune and topologically-protected
surface plasmon polariton in the bandgap of the bulk material. To this end, we
derive a master equation for qubit interactions in a general three-dimensional,
nonreciprocal, inhomogeneous and lossy environment. The environment is
represented exactly, via the photonic Green function. The resulting