A fundamental challenge in digital quantum simulation (DQS) is the control of

inherent errors. These appear when discretizing the time evolution generated by

the Hamiltonian of a quantum many-body system as a sequence of quantum gates,

called Trotterization. Here, we show that quantum localization-by constraining

the time evolution through quantum interference-strongly bounds these errors

for local observables. Consequently, for generic quantum many-body

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It is one of the most important and long-standing issues of physics to derive

the irreversibility out of a time-reversal symmetric equation of motion. The

present paper considers the breaking of the time-reversal symmetry in open

quantum systems and the emergence of an arrow of time. We claim that the

time-reversal symmetric Schr\"{o}dinger equation can have eigenstates that

break the time-reversal symmetry if the system is open in the sense that it has

at least a countably infinite number of states. Such eigenstates, namely the

This whitepaper is an outcome of the workshop Intersections between Nuclear

Physics and Quantum Information held at Argonne National Laboratory on 28-30

March 2018 [www.phy.anl.gov/npqi2018/]. The workshop brought together 116

national and international experts in nuclear physics and quantum information

science to explore opportunities for the two fields to collaborate on topics of

interest to the U.S. Department of Energy (DOE) Office of Science, Office of

We address the estimation of a one-parameter family of isometries taking one

input into two output systems. This primarily allows us to consider imperfect

estimation by accessing only one output system, i.e. through a quantum channel.

Then, on the one hand, we consider separate and adversarial control of the two

output systems to introduce the concept of \emph{privacy of estimation}. On the

other hand we conceive the possibility of separate but cooperative control of

Memory effects can be studied through a conditional past-future correlation,

which measures departure with respect to a conditional past-future independence

valid in a memoryless Markovian regime. In a quantum regime this property leads

to an operational definition of quantum non-Markovianity based on three

consecutive system measurement processes and postselection [Budini, Phys. Rev.

Lett. 121, 240401 (2018)]. Here, we study the conditional past-future

correlation for a qubit system coupled to different dephasing environments.

A two-dimensional spatially and temporally modulated Wannier-Stark system of

ultracold atoms in optical lattices is shown to mimic the behavior of a Dirac

particle. Suitable additional modulations generate an artificial gauge field

which simulates a magnetic field and imposes the use of the full spinor-4 Dirac

equation.

A system of linearly coupled quantum harmonic oscillators can be diagonalized

when the system is dynamically stable using a Bogoliubov canonical

transformation. However, this is just a particular case of more general

canonical transformations that can be performed even when the system is

dynamically unstable. Specific canonical transformations can transform a

quadratic Hamiltonian into a normal form, which greatly helps to elucidate the

underlying physics of the system. Here, we provide a self-contained review of

Molecular electronics is a rapidly developing field focused on using

molecules as the structural basis for electronic components. It is common in

such devices for the system of interest to couple simultaneously to multiple

environments. Here we consider a model comprised of a double quantum dot (or

molecule) coupled strongly to vibrations and weakly to two electronic leads

held at arbitrary bias voltage. The strong vibrational coupling invalidates

treating the bosonic and electronic environments simply as acting additively,

We report a high-resolution terahertz spectroscopic study of quantum spin

dynamics in the antiferromagnetic Heisenberg-Ising spin-chain compound

BaCo$_2$V$_2$O$_8$ as a function of temperature and longitudinal magnetic

field. Confined spinon excitations are observed in an antiferromagnetic phase

below $T_N\simeq 5.5$ K. In a field-induced gapless phase above $B_c=3.8$ T, we

identify many-body string excitations as well as low-energy fractional

psinon/antipsinon excitations by comparing to Bethe-Ansatz calculations. In the

In this work we present an effective Hamiltonian description of the quantum

dynamics of a generalized Lambda system undergoing adiabatic evolution. We

assume the system to be initialized in the dark subspace and show that its

holonomic evolution can be viewed as a conventional Hamiltonian dynamics in an

appropriately chosen extended Hilbert space. In contrast to the existing

approaches, our method does not require the calculation of the non-Abelian

Berry connection and can be applied without any parametrization of the dark