A study of persistent currents and the corresponding induced magnetic field at the nucleus of spherically confined hydrogenic atoms was carried out. The atom was considered to be under the influence of a Hulthén plus a ring-shaped potential. The various confinement parameters prove to be effective in controlling the magnitude of persistent currents as well as induced magnetic fields. This study may prove beneficial for the application of laser pulses which are employed to induce ring currents much stronger than those generated by means of permanent magnetic fields.

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The generation of charge currents and hence induced magnetic field in a spherically bound hydrogen atom by an ultrafast right circularly polarized laser pulse has been studied. The atom is assumed to be under the effect of a Hulthén plus a ring-shaped potential. The simultaneous effect of pulse parameters such as El0, tp and ω0, the cavity radius, r0, and parameters related to the non-central potential has been investigated. These parameters have been found to significantly affect the magnitude of generated current as well as the magnetic field and thus play an important role in determining the response of the system to external laser. The laser pulse is found to produce femtosecond magnetic pulses. Such magnetic pulses have many biomedical applications. Hulthén screening or ring deformation potential reduces the magnitude of current and induced magnetic field for an unbounded atom. On the other hand, for the bounded case, the potential parameters are found to have a positive impact on these quantities.

The spectrum of a particle confined in Hulthén plus ring-shaped potential is obtained by solving the time-independent Schrödinger equation numerically. The effect of potential parameters on various properties of the particle have been investigated in detail. The energy levels, radial matrix elements, oscillator strengths and polarizabilities of the particle have been found to show strong dependence on the confining potential parameters. The presence of the ring potential is found to appreciably alter the angular part of dipole matrix elements. Also, it is shown that the comparison theorem of Quantum Mechanics for energy eigenvalues for four different potentials, viz., Coulomb, Hulthén, Yukawa and Hulthén2 is independent of the presence of ring potential.

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