Both classical and wave-mechanical treatments of wave-like features may be
faced in terms of exact Hamiltonian trajectories, mutually coupled by a "Wave
Potential" function encoded in the structure itself of any Helmholtz-like
equation. In the case of matter waves the Wave Potential establishes a bridge
between the waves and the relevant particles by piloting them along their paths
by means of a "gentle drive" allowing an illuminating insight into
wave-particle duality.

There has been considerable recent interest in matterwave interferometry with
bright solitons in quantum gases with attractive interactions, for applications
such as rotation sensing. We model the quantum dynamics of these systems and
find that the attractive interactions required for the presence of bright
solitons causes quantum phase-diffusion, which severely impairs the
sensitivity. We propose a scheme that partially restores the sensitivity, but
find that in the case of rotation sensing, it is still better to work in a

Recent experiments have demonstrated strong coupling between living bacteria
and light. Here we propose a scheme to infer quantumness of the light-bacteria
correlations, as characterised by the presence of quantum discord, without
requiring any knowledge of their mutual interactions, and by measuring only the
light's degrees of freedom. This is achieved by monitoring the dynamics of the
entanglement between few optical modes (probes) that interact independently

We develop a geometric approach to quantum mechanics based on the concept of
the Tulczyjew triple. Our approach is genuinely infinite-dimensional and
including a Lagrangian formalism in which self-adjoint (Schroedinger) operators
are obtained as Lagrangian submanifolds associated with the Lagrangian. As a
byproduct we obtain also results concerning coadjoint orbits of the unitary
group in infinite dimension, embedding of the Hilbert projective space of pure

We add a confining potential to the Aharonov-Bohm model resulting in no
contact of the particle with the solenoid (border); this is characterized by a
unique self-adjoint extension of the initial Hamiltonian operator. It is shown
that the spectrum of such extension is discrete and the first eigenvalue is
found to be a nonconstant 1-periodic function of the magnetic flux circulation
with a minimum at integers and maximum at half-integer circulations. This is a
rigorous verification of the effect.

It has been shown that a macroscopic system being in a high-temperature
thermal coherent state can be, in principle, driven into a non-classical state
by coupling to a microscopic system. Therefore, thermal coherent states do not
truly represent the classical limit of quantum description. Here, we study the
classical limit of quantum state of a more relevant macroscopic system, namely
the pointer of a detector, after the phase-preserving linear amplification

Author(s): Pedro Nevado, Samuel Fernández-Lorenzo, and Diego Porras
Topological insulating phases are primarily associated with condensed-matter systems, which typically feature short-range interactions. Nevertheless, many realizations of quantum matter can exhibit long-range interactions, and it is still largely unknown the effect that these latter may exert upon t...
[Phys. Rev. Lett. 119, 210401] Published Mon Nov 20, 2017

Author(s): YeJe Park, Jeongmin Shim, S.-S. B. Lee, and H.-S. Sim
When two identical fermions exchange their positions, their wave function gains a phase factor of $−1$. We show that this distance-independent effect can induce nonlocal entanglement in one-dimensional (1D) electron systems having Majorana fermions at the ends. It occurs in the system bulk and has a...
[Phys. Rev. Lett. 119, 210501] Published Mon Nov 20, 2017

Author(s): David Schnoerr, Botond Cseke, Ramon Grima, and Guido Sanguinetti
We consider the problem of computing first-passage time distributions for reaction processes modeled by master equations. We show that this generally intractable class of problems is equivalent to a sequential Bayesian inference problem for an auxiliary observation process. The solution can be appro...
[Phys. Rev. Lett. 119, 210601] Published Mon Nov 20, 2017

Author(s): Emma McKay, Adrian Lupascu, and Eduardo Martín-Martínez
We investigate the validity of two common assumptions in the modeling of superconducting circuits: first, that the superconducting qubits are pointlike and, second, that the UV behavior of the transmission line is not relevant to the qubit dynamics. We show that in the experimentally accessible ultr...
[Phys. Rev. A 96, 052325] Published Mon Nov 20, 2017