Experimental implementation of a quantum computing algorithm strongly relies

on the ability to construct required unitary transformations applied to the

input quantum states. In particular, near-term linear optical computing

requires universal programmable interferometers, capable of implementing an

arbitrary transformation of input optical modes. So far these devices were

composed as a circuit with well defined building blocks, such as balanced

beamsplitters. This approach is vulnerable to manufacturing imperfections

# All

Weyl points, synthetic magnetic monopoles in the 3D momentum space, are the

key features of topological Weyl semimetals. The observation of Weyl points in

ultracold atomic gases usually relies on the realization of high-dimensional

spin-orbit coupling (SOC) for two pseudospin states (% \textit{i.e.,}

spin-1/2), which requires complex laser configurations and precise control of

laser parameters, thus has not been realized in experiment. Here we propose

that robust Wely points can be realized using 1D triple-well superlattices

The vast and growing number of publications in all disciplines of science

cannot be comprehended by a single human researcher. As a consequence,

researchers have to specialize in narrow sub-disciplines, which makes it

challenging to uncover scientific connections beyond the own field of research.

Thus access to structured knowledge from a large corpus of publications could

help pushing the frontiers of science. Here we demonstrate a method to build a

semantic network from published scientific literature, which we call SemNet. We

Two time-reversal quantum key distribution (QKD) schemes are the quantum

entanglement based device-independent (DI)-QKD and

measurement-device-independent (MDI)-QKD. The recently proposed twin field

(TF)-QKD, also known as phase-matching (PM)-QKD, has improved the key rate

bound from $O\left( \eta \right )$ to $O\left( \sqrt {\eta} \right )$ with

$\eta$ the channel transmittance. In fact, TF-QKD is a kind of MDI-QKD but

based on single-photon detection. In this paper, we propose a different PM-QKD

We analyse the charging process of quantum batteries with general harmonic

power. To describe the charge efficiency, we introduce the charge saturation

and the charging power, and divide the charging mode into the saturated

charging mode and the unsaturated charging mode. The relationships between the

time-dependent charge saturation and the parameters of general driving field

are discussed both analytically and numerically. And according to the Floquet

The Carnot cycle combines reversible isothermal and adiabatic strokes to

obtain optimal efficiency, at the expense of a vanishing power output. Here, we

construct quantum Carnot-analog cycles, operating irreversibly at non-vanishing

power. Swift thermalization is obtained utilizing shortcut to equilibrium

protocols and the isolated strokes employ frictionless shortcut to adiabaticity

protocols. We solve the dynamics for a working medium composed of a particle in

We consider a fractional generalization of two-dimensional (2D)

quantum-mechanical Kepler problem corresponding to 2D hydrogen atom. Our main

finding is that the solution for discreet spectrum exists only for $\mu>1$

(more specifically $1 < \mu \leq 2$, where $\mu=2$ corresponds to "ordinary" 2D

hydrogenic problem), where $\mu$ is the L\'evy index. We show also that in

fractional 2D hydrogen atom, the orbital momentum degeneracy is lifted so that

its energy starts to depend not only on principal quantum number $n$ but also

We introduce a model to study the collisions of two ultracold diatomic

molecules in one dimension interacting via pairwise potentials. We present

results for this system, and argue that it offers lessons for real molecular

collisions in three dimensions. We analyze the distribution of the adiabatic

potentials in the hyperspherical coordinate representation as well as the

distribution of the four-body bound states in the adiabatic approximation (i.e.

no coupling between adiabatic channels). It is found that while the adiabatic

We analyse quasi-periodically driven quantum systems that can be mapped

exactly to periodically driven ones and find Floquet Time Spirals in analogy

with spatially incommensurate spiral magnetic states. Generalising the

mechanism to many-body systems we discover that a form of discrete

time-translation symmetry breaking can also occur in quasi-periodically driven

systems. We construct a discrete time quasi-crystal stabilised by many-body

localisation, which persists also under perturbations that break the

We present a detailed study of the topological Schwinger model

[$\href{this http URL}{Phys. \; Rev.\; D \; {\bf

99},\;014503 \; (2019)}$], which describes (1+1) quantum electrodynamics of an

Abelian $U(1)$ gauge field coupled to a symmetry-protected topological matter

sector, by means of a class of $\mathbb{Z}_N$ lattice gauge theories. Employing

density-matrix renormalization group techniques that exactly implement Gauss'