At zero energy the Dirac equation has interesting behaviour. The asymmetry in
the number of spin up and spin down modes is determined by the topology of both
space and the gauge field in which the system sits. An analogous phenomenon
also occurs in electromagnetism. Writing Maxwell's equations in a Dirac-like
form, we identify cases where a material parameter plays the role of energy. At
zero energy we thus find electromagnetic modes that are indifferent to local

We consider a protocol for sharing quantum states using continuous variable
systems. Specifically we introduce an encoding procedure where bosonic modes in
arbitrary secret states are mixed with several ancillary squeezed modes through
a passive interferometer. We derive simple conditions on the interferometer for
this encoding to define a secret sharing protocol and we prove that they are
satisfied by almost any interferometer. This implies that, if the

Quantum tomography is currently ubiquitous for testing any implementation of
a quantum information processing device. Various sophisticated procedures for
state and process reconstruction from measured data are well developed and
benefit from precise knowledge of the model describing state preparation and
the measurement apparatus. However, physical models suffer from intrinsic
limitations as actual measurement operators and trial states cannot be known

The electron and positron magnetic moments are the most precise prediction of
the standard model of particle physics. The most accurate measurement of a
property of an elementary particle has been made to test this result. A new
experimental method is now being employed in an attempt to improve the
measurement accuracy by an order of magnitude. Positrons from a "student
source" now suffice for the experiment. Progress toward a new measurement is

Solid-state experimental realizations of Majorana bound states are based on
materials with strong intrinsic spin-orbit interactions. In this work, we
explore an alternative approach where spin-orbit coupling is induced
artificially through a non-uniform magnetic field that originates from an array
of micromagnets. Using a recently developed optimization algorithm, we find
suitable micromagnet geometries for the emergence of topological
superconductivity in a one-dimensional wire without intrinsic spin-orbit

High-fidelity entangling quantum gates based on Rydberg interactions are
required for scalable quantum computing with neutral atoms. Their realization,
however, meets a major stumbling block -- the motion-induced dephasing of the
transition between the ground and Rydberg states. By using quantum interference
between different detuned Rabi oscillations, we propose a practical scheme to
realize a class of accurate entangling Rydberg quantum gates subject to a

The so-called information-thermodynamics link created by a thought experiment of Szilard became a
core of modern orthodoxy in the field of quantum information and resources theory in quantum
thermodynamics. We recall existing objections against standard interpretation of Szilard engine
operation and illustrate them by two quantum models: a particle in a box with time-dependent thin
potential barrier and the spin-boson model. The consequences of the emerging superselection rules

In this paper we present a rigorous method for deciding whether a birational three point mapping
that has the singularity confinement property is integrable or not, based only on the structure of
its (confined) singularity patterns. We also explain how the exact value of the dynamical degree for
such a mapping may be deduced from the singularity patterns.

The B 1 vertex model is studied by the off-diagonal Bethe ansatz method. New closed operator product
identities of the fused transfer matrices are obtained by using the fusion technique. Based on them
and the asymptotic behaviors as well as the values of the fused transfer matrices at certain points,
the exact solutions of the B 1 model with periodic and with integrable off-diagonal open boundary
conditions are obtained. We find that the degree of the polynomial of the inhomogeneous T   −   Q

Author(s): Xudan Chai, Yi-Ping Lu, An-ning Zhang, and Qing Zhao
Quantum state tomography is of crucial importance in assessing the quality of quantum information processing devices. Tomography fundamentally requires both experiments and data processing resources, which increase exponentially with the size of qubits. We propose using phase lift to precisely chara...
[Phys. Rev. A 99, 042321] Published Fri Apr 12, 2019