Photoionization of confined hydrogen atom by short laser pulses

Two Photon Processes in an Atom Confined in Gaussian Potential

“…Also, CdSe quantum rods have been shown to exhibit four times larger TPA as compared to quantum dots of the same mass [24]. Similar studies have recently been initiated with much vigor in the case of atoms and ions confined in a variety of plasma environments and other confinements [25][26][27][28][29][30][31][32][33][34][35][36]. Some works on two-photon transitions in atoms or ions employing the Ion-Sphere model [37] for strongly-coupled plasmas were also reported in the literature [34,38,39].…”

“…The atom is supposed to be confined spherically with impenetrable walls, such that the wave functions vanish at the boundary r = r 0 , where r 0 is assumed to have a fixed value of 50 a.u. This is the case of loose spherical confinement as discussed in earlier texts [25][26][27][28][29][30]. The energy spectrum and dipole matrix elements of the system have been evaluated by solving the corresponding radial Schrödinger equation with the aim to study the two-photon spectra which refers to the excitation process generated by the simultaneous absorption of two less-energetic photons under sufficiently intense laser illumination.…”

“…Optical properties like oscillator strength and polarizability had been calculated for a hydrogen atom under the effect of Gaussian potential and loose spherical confinement in our earlier work [26]. The method used for solving the Schrödinger equation is based on Bernstein-polynomials (B-polynomials) and is detailed elsewhere [29][30][31][32]43,44]. Only the basic outline of the approach followed for the present work has been mentioned in the following text.…”

Two-photon transitions in confined hydrogenic atoms

“…It is well-known that in interpretation of various data associated with astrophysics, hot plasma etc., basic understanding of atomic excitation and ionization is required since these processes taking place in plasma environment provide important information about plasma. The processes which have recently attracted much attention are laser-assisted collisions in plasma [9][10][11][12] and response of confined atoms to short and intense laser pulses [13,14]. The plasma environment considered here is Debye plasma where Debye screening length, λ D = k B T /(4πe 2 n), being a function of the plasma temperature T and its density n, plays an important role.…”

“…If, in addition to the screening potentials, there happens to be a spherical confinement, then the atom shows a drastic change in the spectrum. For example, Lumb et al [14,21] have shown that there are very few bound states if confining radius r c is very small (r c 10 a.u.). So, spherical confinement in addition to screened potential forms a new confining potential where atomic and molecular systems are yet to be explored in detail.…”