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In Thouless pumping, although non-flat band has no effects on the
quantization of particle transport, it induces wave-packet dispersion which
hinders the practical applications of Thouless pumping. Indeed, we find that
the dispersion mainly arises from the dynamical phase difference between
individual Bloch states. Here we propose two efficient schemes to suppress the
dispersion in Thouless pumping: a re-localization echo protocol and a
high-order tunneling suppression protocol. In the re-localization echo

We investigate the entanglement measures of tripartite W-State and GHZ-state
in noninertial frame through the coordinate transformation between Minkowski
and Rindler. First it is shown that all three qubits undergo in a uniform
acceleration $a$ of W-State, we find that the one-tangle, two-tangle, and
$\pi$-tangle decrease when the acceleration parameter $r$ increases, and the
two-tangle cannot arrive to infinity of the acceleration. Next we show that the

Quantum computers will allow calculations beyond existing classical
computers. However, current technology is still too noisy and imperfect to
construct a universal digital quantum computer with quantum error correction.
Inspired by the evolution of classical computation, an alternative paradigm
merging the flexibility of digital quantum computation with the robustness of
analog quantum simulation has emerged. This universal paradigm is known as
digital-analog quantum computing. Here, we introduce an efficient

It is well-known that observing nonlocal correlations allows us to draw
conclusions about the quantum systems under consideration. In some cases this
yields a characterisation which is essentially complete, a phenomenon known as
self-testing. Self-testing becomes particularly interesting if we can make the
statement robust, so that it can be applied to a real experimental setup. For
the simplest self-testing scenarios the most robust bounds come from the method

Much of modern metrology and communication technology encodes information in
electromagnetic waves, typically as an amplitude or phase. While current
hardware can perform near-ideal measurements of photon number or field
amplitude, to date no device exists that can even in principle perform an ideal
phase measurement. In this work, we implement a single-shot canonical phase
measurement on a one-photon wave packet, which surpasses the current standard
of heterodyne detection and is optimal for single-shot phase estimation. By

We consider the logarithmic negativity and related quantities of time
evolution operators. We study free fermion, compact boson, and holographic
conformal field theories (CFTs) as well as numerical simulations of random
unitary circuits and integrable and chaotic spin chains. The holographic
behavior strongly deviates from known non-holographic CFT results and displays
clear signatures of maximal scrambling. Intriguingly, the random unitary
circuits display nearly identical behavior to the holographic channels.

In a special representation of complex action theory that we call
``future-included'', we study a harmonic oscillator model defined with a
non-normal Hamiltonian $\hat{H}$, in which a mass $m$ and an angular frequency
$\omega$ are taken to be complex numbers. In order for the model to be sensible
some restrictions on $m$ and $\omega$ are required. We draw a phase diagram in
the plane of the arguments of $m$ and $\omega$, according to which the model is
classified into several types. In addition, we formulate two pairs of

A three-state system subjected to a time-dependent Hamiltonian whose bare
energies undergo one or more crossings, depending on the relevant parameters,
is considered, also taking into account the role of dissipation in the
adiabatic following of the Hamiltonian eigenstates. Depending on the fact that
the bare energies are equidistant or not, the relevant population transfer
turns out to be very sensitive to the environmental interaction or relatively
robust. The physical mechanisms on the basis of this behavior are discussed in

We analyze the dynamics of multiparticle discrete-time quantum walk on the
two-dimensional lattice, with an interaction inspired on a classical model for
gas collision, called HPP model. In this classical model, the direction of
motion changes only when the particles collide head-on, preserving momentum and
energy. In our quantum model, the dynamics is driven by the usual quantum-walk
evolution operator if the particles are on different nodes, and is driven by

Floquet engineering or coherent time periodic driving of quantum systems has
been successfully used to synthesize Hamiltonians with novel properties. In
ultracold atomic systems, this has led to experimental realizations of
artificial gauge fields, topological band structures, and observation of
dynamical localization, to name just a few. Here we present a Floquet-based
framework to stroboscopically engineer Hamiltonians with spatial features and
periodicity below the diffraction limit of light used to create them by

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