Geometric phase is insensitive to certain local disturbances due to the

global properties accumulated through a closed loop in the parameter space. It

can be utilized to realize high-fidelity logic gates for geometric quantum

computing. Moveover in the degenerate subspace, non-Abelian geometric phase

leads to quantum holonomic gates. In this work, we propose a novel scheme for

holonomic gates using Rydberg atoms under the detuning-controllable drivings,

which can be considerably improved by the counterdiabatic method. In

# All

Quantum droplets may form out of a gaseous Bose-Einstein condensate,

stabilized by quantum fluctuations beyond mean field. We show that multiple

singly-quantized vortices may form in these droplets at moderate angular

momenta in two dimensions. Droplets carrying these precursors of an Abrikosov

lattice remain self-bound for certain timescales after switching off an initial

harmonic confinement. Furthermore, we examine how these vortex-carrying

droplets can be formed in a more pertubation-resistant setting, by starting

Self-testing is a method to infer the underlying physics of a quantum

experiment in a black box scenario. As such it represents the strongest form of

certification for quantum systems. In recent years a considerable self-testing

literature has been developed, leading to progress in related

device-independent quantum information protocols and deepening our

understanding of quantum correlations. In this work we give a thorough and

self-contained introduction and review of self-testing and its application to

We study the dynamical behavior of nonlinear coupling in a quantum wave

equation of a logarithmic type. Using statistical mechanical arguments for a

large class of many-body systems, this coupling is shown to be related to

temperature which is a thermodynamic conjugate to the Everett-Hirschman's

quantum information entropy. A combined quantum-mechanical and

field-theoretical model is proposed, which leads to a logarithmic equation with

variable nonlinear coupling. We study its properties and present arguments

The quantum satellite is a cornerstone towards practical free-space quantum

network and overcomes the photon loss over large distance. However, challenges

still exist including real-time all-location coverage and multi-node

construction, which may be complemented by the diversity of modern drones. Here

we demonstrate the first drone-based entanglement distribution at all-weather

conditions over 200 meters (test field limited), and the

Clauser-Horne-Shimony-Holt S-parameter exceeds 2.49, within 35 kg take-off

We significantly reduce the cost of factoring integers and computing discrete

logarithms over finite fields on a quantum computer by combining techniques

from Griffiths-Niu 1996, Zalka 2006, Fowler 2012, Eker{\aa}-H{\aa}stad 2017,

Eker{\aa} 2017, Eker{\aa} 2018, Gidney-Fowler 2019, Gidney 2019. We estimate

the approximate cost of our construction using plausible physical assumptions

for large-scale superconducting qubit platforms: a planar grid of qubits with

Contextuality is a signature of operational nonclassicality in the outcome

statistics of an experiment. This notion of nonclassicality applies to a

breadth of physical phenomena. Here, we establish its relation to two

fundamental nonclassical entities in quantum theory; measurement

incompatibility and steering. We show that each is necessary and sufficient the

failure of operational contextuality. We exploit the established connection to

contextuality to provide a novel approach to problems in measurement

To achieve scalable quantum computing, improving entangling-gate fidelity and

its implementation-efficiency are of utmost importance. We present here a

linear method to construct provably power-optimal entangling gates on an

arbitrary pair of qubits on a trapped-ion quantum computer. This method

leverages simultaneous modulation of amplitude, frequency, and phase of the

beams that illuminate the ions and, unlike the state of the art, does not

require any search in the parameter space. The linear method is extensible,

Uncertainty relation is one of the fundamental principle in quantum mechanics

and plays an important role in quantum information science. We experimentally

test the error-disturbance uncertainty relation (EDR) with continuous variables

for Gaussian states. Two conjugate continuous-variable observables, amplitude

and phase quadratures of an optical mode, are measured simultaneously by using

a heterodyne measurement system. The EDR with continuous variables for a

coherent state, a squeezed state and a thermal state are verified

A conceptually simple model for strongly interacting compact U(1) lattice

gauge theory is expressed as operators acting on qubits. The number of

independent gauge links is reduced to its minimum through the use of Gauss's

law. The model can be implemented with any number of qubits per gauge link, and

a choice as small as two is shown to be useful. Real-time propagation and

real-time collisions are observed on lattices in two spatial dimensions. The

extension to three spatial dimensions is also developed, and a first look at