Expectation value (quantum mechanics)

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Semiclassical trajectory-based methods are computational techniques that approximate solutions to the time-dependent Schrödinger equation by using information from classical trajectories equipped with evolving phases or width matrices. These additional structures to the classical trajectory enable semiclassical methods to go beyond purely classical descriptions and to capture quantum effects, at least approximately. While single-trajectory semiclassical methods, such as the thawed Gaussian approximation,

Differential privacy (DP) is a widely used framework for protecting sensitive information in data analysis and machine learning. With growing interest in quantum computing, substantial effort has gone into extending DP to quantum algorithms. However, many existing formulations emphasize global state distinguishability or privacy for channels that output quantum states, which is often misaligned with settings where the final output consists of classical measurement data, as in both fault-tolerant and near-te

Quantitative phase imaging (QPI) refers to label-free techniques that produce images containing morphological information. In this chapter, we focus on 2D phase imaging with a holographic setup. In such a setting, the complex-valued measurements contain both intensity and phase information. The phase is related to the distribution of the refractive index of the underlying specimen. In practice, the collected phase happens to be wrapped (i.e., modulo 2π of the original phase) and one gains quantitative infor

The PETALE experimental program in the CROCUS reactor intends to provide integral measurements on reactivity worth and dosimetry measurement to constrain nuclear data relative to stainless steel heavy reflectors. The experimental setup consists in eight su ...

We report on the magnetic properties of Fe and Co adatoms on a Cu2N/Cu(100)-c(2 x 2) surface investigated by x-ray magnetic dichroism measurements and density functional theory (DFT) calculations including the local coulomb interaction. We compare these results with properties formerly deduced from STM spin excitation spectroscopy (SES) performed on the individual adatoms. In particular we focus on the values of the local magnetic moments determined by XMCD compared to the expectation values derived from th

Initial value representations are constructed to avoid the search for trajectories that are only defined in semiclassical approximations by their boundary conditions. We show how to incorporate these procedures within the full Weyl representation, so that ...

The theory of photofragments angular momentum polarization is applied to the photodetachment of an electronically excited alkali atom from a helium nanocluster (N = 200). The alignment of the electronic angular momentum of the bare excited alkali atoms pro ...

Owing to its detailed diagnostics, feasibility of parameter scans, and relatively simple configuration, the basic plasma physics experiment TORPEX is an ideal testbed in which to perform experiment/simulation comparisons and to contribute to the establishment of the validation methodology. Focusing on observables related to Langmuir probe measurements, we consider a number of physical quantities that can be used as observables for experiment/simulation comparison. We classify the observables according to a

Starting from the quantum-Boltzmann equation derived in a previous paper, we study the irreversible evolution of an electron gas in the one-particle phase space. The connection with phase space is established by expressing one-electron states in terms of t ...

The sign of the theoretically predicted steric asymmetry S in rotational inelastic state resolved molecule–atom collisions is questioned. It is shown that the sign of the T-matrix obtained on a basis of non-oriented rotational states of the molecule depends on the choice of the Jacobi coordinates in which the collision problem is solved. Explicit expressions for the state-to-state dependence of the integral and differential cross-sections for oriented and non-oriented molecules are presented. The effect of

The problem of controlling nonlinear nonminimum-phase systems is considered, where standard input-output feedback linearization leads to unstable internal dynamics. This problem is handled here by using the observability normal form in conjunction with input-output linearization. The system is feedback linearized upon neglecting a part of the system dynamics, with the neglected part being considered as a perturbation. A linear controller is designed to accommodate the perturbation resulting from the approxi

The incorporation of In in the growth of crescent-shaped In0.12Ga0.88As quantum wires embedded in (AlAs)(4)(GaAs)(8) superlattice barriers is studied in atomic detail using cross-sectional scanning tunneling microscopy. It is found that the In distribution in both the surface and the first subsurface layer can be atomically resolved in the empty- and filled-state images, respectively. Strong In segregation is seen at the InGaAs/GaAs interfaces, but neither an expected enhancement of the In concentration at

Expectation value (quantum mechanics)

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Phase-space discretization methods for the semiclassical Herman-Kluk propagator and applications to spectroscopy

A general framework for differentially private quantum measurements

Regularizing Neural Network for Phase Unwrapping

Dosimetry modeling and experimental validation for the PETALE program in the CROCUS reactor

Comparing XMCD and DFT with STM spin excitation spectroscopy for Fe and Co adatoms on

Initial or final values for semiclassical evolutions in the Weyl–Wigner representation

Communication: Angular momentum alignment and fluorescence polarization of alkali atoms photodetached from helium nanodroplets

The validation project on the TORPEX basic plasma physics experiment

Irreversible evolution of many-electron systems: From the quantum-Boltzmann equation toward the semi-classical Boltzmann equation

Sign of the state-to-state steric asymmetry of rotationally inelastic atom-molecule collisions

Approximate Input-Output Linearization of Nonlinear Systems Using the Observability Normal Form

Indium Distribution in Ingaas Quantum Wires Observed with the Scanning Tunneling Microscope