Confined atoms

A far-off resonance trap (FORT), in contrast, uses tire dipole force ratlier tlian tire spontaneous force to confine atoms and can therefore operate far from resonance witli negligible population of excited states. A hybrid MOT/dipole-force trap was used by a NIST-Maryland collaboration [26] to study cold collisions, and a FORT was... 

Before starting the discussion on confined atoms, we shall briefly describe the simplest standard confined quantum mechanical system in three dimensions (3-D), namely the particle-in-a-(spherical)-box (PIAB) model [1], The analysis of this system is useful in order to understand the main characteristics of a confined system. Let us note that all other spherically confined systems with impenetrable walls located at a certain radius, Rc, transform into the PIAB model in the limit of Rc —> 0. For the sake of simplicity, we present the model in one-dimension (1-D). In atomic units (a.u.) (me=l, qc 1, and h = 1), the Schrodinger equation for an electron confined in one-dimensional box is... 

This problem does not admit an analytic solution, but it has been solved with several techniques to obtain very accurate values [4—6]. In our case, we will use a simple technique to obtain many of the characteristics exhibited by the confined atoms. 

The role of instabilities involving confined impurity atoms has been investigated by Mtiser using a model in which two one-dimensional (1-D) or 2-D surfaces were separated by a very low concentration of confined atoms and slid past one another.25 The motion of the confined atoms was simulated with Langevin dynamics where the interactions between these atoms were neglected and the atom-wall interactions were described by... 

Generation of orbital densities for free and confined atoms through... 

In this work, we use the confined atoms model, with hard walls, to estimate the pressure on confined Ca, Sr, and Ba atoms. With this approach, we will give an upper limit to the pressure, because it is well known that the Dirichlet boundary conditions give an overestimation to this quantity. By using this approach, we obtain the profiles of some electronic properties... 

Pressure Effects on the Electronic Properties of Ca, Sr, and Ba by the Confined Atoms Model... 

Table 1 Transition pressures for Ca, Sr and Ba estimated by the confined atom model. Pressure in GPa and...

Since the 5-potential model assumes that the size ra of the confined atom is much smaller than the size Rc of the fullerene cage, ra << Rc, only... 

The presented data illustrate the noticeable sensitivity of threshold values of the photoionization cross sections of confined atoms to the principal quantum number n. Indeed, as seen from Figure 5, the photoionization cross section anoticeably increases, whereas er 5 decreases, at threshold, compared to the free Ne atom. As a result, for confined Ne, the threshold... 

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