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An interesting aspect of antiferromagnetic quantum spin ladders, with
complete dimer coverings, is that the wave function can be recursively
generated by estimating the number of coverings in the valence bond basis,
which follow the fabled Fibonacci sequence. In this work, we derive generalized
forms of this sequence for multi-legged and doped quantum spin ladders, which
allow the corresponding dimer-covered state to be recursively generated. We
show that these sequences allow for estimation of physically and

Quantum nonlocal correlations mainly contain quantum entanglement, Bell
nonlocality and Einstein-Podolsky-Rosen steering. Recently, coherence, as an
important quantum resource, plays a crucial role in quantum information
processing. Hence, revealing the mutual relations between nonlocal correlations
and coherence has attracted much attention. Here we investigate the
correlations of the tripartite states (the W-class states) based on the
bipartite correlation measures, such as entanglement (concurrence), coherence

We propose to use the eigenfunctions of a one-electron model Hamiltonian to
perform electron-nucleus mean field configuration interaction (EN-MFCI)
calculations. The potential energy of our model Hamiltonian corresponds to the
Coulomb potential of an infinite wire with charge $Z$ distributed according to
a Gaussian function. The time independent \sch equation for this Hamiltonian is
solved perturbationally in the limit of small amplitude vibration (Gaussian
function width close to zero).

Quantum sensors have recently achieved to detect the magnetic moment of few
or single nuclear spins and measure their magnetic resonance (NMR) signal.
However, the spectral resolution, a key feature of NMR, has been limited by
relaxation of the sensor to a few kHz at room temperature. The spectral
resolution of NMR signals from single nuclear spins can be improved by, e.g.,
using quantum memories, however at the expense of sensitivity. Classical
signals on the other hand can be measured with exceptional spectral resolution

We extend the theory of perturbations of KMS states to some class of
unbounded perturbations using noncommutative Lp-spaces. We also prove certain
stability of the domain of the Modular Operator associated to a
||.||p-continuous state. This allows us to define an analytic multiple-time KMS
condition and to obtain its analyticity together with some bounds to its norm.

In this manuscript, we present analytical solution of the Klein-Gordon
equation with the multi-parameter q-deformed Woods-Saxon type potential energy
under the spin symmetric limit in $(1+1)$ dimension. In the scattering case, we
obtain the reflection and transmission probabilities and prove the conservation
of the total probability. Moreover, we analyze the correlation between the
potential parameters with the reflection and transmission probabilities. In the

It is well known that in a two-slit interference experiment, acquiring
which-path information about the particle, leads to a degrading of the
interference. It is argued that path-information has a meaning only when one
can umabiguously tell which slit the particle went through. Using this idea,
two duality relations are derived for the general case where the two paths may
not be equally probable, and the two slits may be of unequal widths. These
duality relations, which are inequalities in general, saturate for all pure

A fundamental question in the theory of quantum computation is to understand
the ultimate space-time resource costs for performing a universal set of
logical quantum gates to arbitrary precision. To date, all proposed schemes for
implementing a universal logical gate set, such as magic state distillation or
code switching, require a substantial space-time overhead, including a time
overhead that necessarily diverges in the limit of vanishing logical error

We propose a scheme of fast three-qubit Toffoli quantum gate for ultracold
neutral-atom qubits. The scheme is based on the Stark-tuned three-body
F\"{o}rster resonances, which we have observed in our recent experiment
[D.B.Tretyakov et al., Phys.Rev.Lett. 119, 173402 (2017)]. The three-body
resonance corresponds to a transition when the three interacting atoms change
their states simultaneously, and it occurs at a different dc electric field
with respect to the two-body F\"{o}rster resonance. A combined effect of

We demonstrate theoretically and experimentally a high level of control of
the four-wave mixing process in an inert gas filled inhibited-coupling guiding
hollow-core photonic crystal fiber in order to generate photon pairs. The
specific multiple-branch dispersion profile in such fibers allows both
entangled and separable bi-photon states to be produced. By controlling the
choice of gas, its pressure and the fiber length, we experimentally generate
various joint spectral intensity profiles in a stimulated regime that is