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Phase distortions, or aberrations, can negatively influence the performance
of an optical imaging system. Through the use of position-momentum entangled
photons, we nonlocally correct for aberrations in one photon's optical path by
intentionally introducing the complementary aberrations in the optical path of
the other photon. In particular, we demonstrate the simultaneous nonlocal
cancellation of aberrations that are of both even and odd order in the photons'

Two-dimensional Nuclear Magnetic Resonance (NMR) is essential in molecular
structure determination. The Nitrogen-Vacancy (NV) center in diamond has been
proposed and developed as an outstanding quantum sensor to realize NMR in
nanoscale. In this work, we develop a scheme for two-dimensional nanoscale NMR
spectroscopy based on quantum controls on an NV center. We carry out a proof of
principle experiment on a target of two coupled $^{13}$C nuclear spins in
diamond. A COSY-like sequences is used to acquire the data on time domain,

Recent years have witnessed a growing interest in topics at the intersection
of many-body physics and complexity theory. Many-body physics aims to
understand and classify emergent behavior of systems with a large number of
particles, while complexity theory aims to classify computational problems
based on how the time required to solve the problem scales as the problem size
becomes large. In this work, we use insights from complexity theory to classify
phases in interacting many-body systems. Specifically, we demonstrate a

Deployment of quantum technology in space provides opportunities for new
types of precision tests of gravity. On the other hand, the operational demands
of such technology can make previously unimportant effects practically
relevant. We describe a novel optical interferometric red-shift measurement and
a measurement scheme designed to witness possible spin-gravity coupling
effects.

EPR-steering refers to the ability of one observer to convince a distant
observer that they share entanglement by making local measurements. Determining
which states allow a demonstration of EPR-steering remains an open problem in
general, even for the simplest case of two qubits. Here, we outline and
demonstrate a method of constructing new classes of two-qubit states which are
non-steerable by arbitrary projective measurements, from consideration of local

The Riemann hypothesis, one of the most important open problems in pure
mathematics, implies the most profound secret of prime numbers. One of the most
interesting approaches to solve this hypothesis is to connect the problem with
the spectrum of the physical Hamiltonian of a quantum system. However, none of
the proposed quantum Hamiltonians have been experimentally feasible. Here, we
report the first experiment to identify the first non-trivial zeros of the

We analyze the class of Generalized Double Semion (GDS) models in arbitrary
dimensions from the point of view of lattice Hamiltonians. We show that on a
$d$-dimensional spatial manifold $M$ the dual of the GDS is equivalent, up to
constant depth local quantum circuits, to a group cohomology theory tensored
with lower dimensional cohomology models that depend on the manifold $M$. We
comment on the space-time topological quantum field theory (TQFT)
interpretation of this result. We also investigate the GDS in the presence of

The fast forward scheme of adiabatic quantum dynamics is applied to finite
regular spin clusters with various geometries and the nature of driving
interactions is elucidated. The fast forward is the quasi-adiabatic dynamics
guaranteed by regularization terms added to the reference Hamiltonian, followed
by a rescaling of time with use of a large scaling factor. With help of the
regularization terms consisting of pair-wise and 3-body interactions, we apply
the proposed formula (Phys. Rev.A 96, 052106(2017)) to regular triangle and

The properties of ground state of spin-$\frac{1}{2}$ kagome antiferromagnetic
Heisenberg (KAFH) model have attracted considerable interest in the past few
decades, and recent numerical simulations reported a spin liquid phase. The
nature of the spin liquid phase remains unclear. For instance, the interplay
between symmetries and $Z_2$ topological order leads to different types of
$Z_2$ spin liquid phases. In this paper, we develop a numerical simulation
method based on symmetric projected entangled-pair states (PEPS), which is

For quantum communications, the use of Earth-orbiting satellites to extend
distances has gained significant attention in recent years, exemplified in
particular by the launch of the Micius satellite in 2016. The performance of
applied protocols such as quantum key distribution (QKD) depends significantly
upon the transmission efficiency that can be achieved through the turbulent
atmosphere, which is especially challenging for ground-to-satellite uplink
scenarios. Adaptive optics (AO) techniques have been used in astronomical,

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