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We propose to use the eigenfunctions of a one-electron model Hamiltonian to

perform electron-nucleus mean field configuration interaction (EN-MFCI)

calculations. The potential energy of our model Hamiltonian corresponds to the

Coulomb potential of an infinite wire with charge $Z$ distributed according to

a Gaussian function. The time independent \sch equation for this Hamiltonian is

solved perturbationally in the limit of small amplitude vibration (Gaussian

function width close to zero).

Quantum sensors have recently achieved to detect the magnetic moment of few

or single nuclear spins and measure their magnetic resonance (NMR) signal.

However, the spectral resolution, a key feature of NMR, has been limited by

relaxation of the sensor to a few kHz at room temperature. The spectral

resolution of NMR signals from single nuclear spins can be improved by, e.g.,

using quantum memories, however at the expense of sensitivity. Classical

signals on the other hand can be measured with exceptional spectral resolution

We extend the theory of perturbations of KMS states to some class of

unbounded perturbations using noncommutative Lp-spaces. We also prove certain

stability of the domain of the Modular Operator associated to a

||.||p-continuous state. This allows us to define an analytic multiple-time KMS

condition and to obtain its analyticity together with some bounds to its norm.

In this manuscript, we present analytical solution of the Klein-Gordon

equation with the multi-parameter q-deformed Woods-Saxon type potential energy

under the spin symmetric limit in $(1+1)$ dimension. In the scattering case, we

obtain the reflection and transmission probabilities and prove the conservation

of the total probability. Moreover, we analyze the correlation between the

potential parameters with the reflection and transmission probabilities. In the

It is well known that in a two-slit interference experiment, acquiring

which-path information about the particle, leads to a degrading of the

interference. It is argued that path-information has a meaning only when one

can umabiguously tell which slit the particle went through. Using this idea,

two duality relations are derived for the general case where the two paths may

not be equally probable, and the two slits may be of unequal widths. These

duality relations, which are inequalities in general, saturate for all pure

A fundamental question in the theory of quantum computation is to understand

the ultimate space-time resource costs for performing a universal set of

logical quantum gates to arbitrary precision. To date, all proposed schemes for

implementing a universal logical gate set, such as magic state distillation or

code switching, require a substantial space-time overhead, including a time

overhead that necessarily diverges in the limit of vanishing logical error

We propose a scheme of fast three-qubit Toffoli quantum gate for ultracold

neutral-atom qubits. The scheme is based on the Stark-tuned three-body

F\"{o}rster resonances, which we have observed in our recent experiment

[D.B.Tretyakov et al., Phys.Rev.Lett. 119, 173402 (2017)]. The three-body

resonance corresponds to a transition when the three interacting atoms change

their states simultaneously, and it occurs at a different dc electric field

with respect to the two-body F\"{o}rster resonance. A combined effect of

We demonstrate theoretically and experimentally a high level of control of

the four-wave mixing process in an inert gas filled inhibited-coupling guiding

hollow-core photonic crystal fiber in order to generate photon pairs. The

specific multiple-branch dispersion profile in such fibers allows both

entangled and separable bi-photon states to be produced. By controlling the

choice of gas, its pressure and the fiber length, we experimentally generate

various joint spectral intensity profiles in a stimulated regime that is

We study algorithms for solving Subtraction games, which sometimes are

referred to as one-heap Nim games. We describe a quantum algorithm which is

applicable to any game on DAG, and show that its query compexity for solving an

arbitrary Subtraction game of $n$ stones is $O(n^{3/2}\log n)$. The best known

deterministic algorithms for solving such games are based on the dynamic

programming approach. We show that this approach is asymptotically optimal and

that classical query complexity for solving a Subtraction game is generally

We show that a special type of measurements, called symmetric informationally

complete positive operator-valued measures (SIC POVMs), provide a stronger

entanglement detection criterion than the computable cross-norm or realignment

criterion based on local orthogonal observables. As an illustration, we

demonstrate the enhanced entanglement detection power in simple systems of

qubit and qutrit pairs. This observation highlights the significance of SIC

POVMs for entanglement detection.