The response of an atomic hydrogen system in the presence of an intense ultrashort laser pulse is investigated by direct integration of the time-dependent Schrödinger equation. The target wavefunctions are expanded in terms of an accurate and discrete L2 basis, which is optimized for convergence, making the approach more realistic. We have studied the variation of probability of ionization with laser pulse parameters such as the intensity, frequency, chirp rate and pulsewidth. The need for ultrashort pulses is highlighted by the results and we also found that chirped pulses provide a more efficient way of population transfer when compared with a non-chirped pulse.

In this work, we present the effects of an external electric field on the Shannon entropy sum of a spherically confined hydrogenic atom. The confinement considered is of the impenetrable hard wall type. The electric field modifies the spectrum of the confined hydrogenic system, which results in avoided crossings among the energy levels of the system, with strong competition between the Coulombic and hard wall potential. The results presented indicate that the electric field is a strong candidate to modify information theoretic measures. In addition, we examine the effects of field strength, nuclear charge and hard walls on the minima/maxima structure of the entropic sum.

We consider the electron bound in the conduction band of a coupled asymmetric double quantum well (ADQW) interacting with static as well as strong monochromatic field in terahertz (THz) region. We use non-perturbative Floquet theory to study the static field and quantum well (QW) system in the presence of strong laser fields. We show that the intersubband dynamics gets modified due to the static field. The sensitivity to the ratio of strengths of static and laser field (E s /E 0 ) of the state populations can be used in various optoelectronic device applications.

No abstract

No abstract