Complete population transfer by a zero-area pulse (6 pages)

Justin Z. Gong, Sydney Rice

Kh. Yu. Rakhimov

G. S. Vasilev, Nikolay V. Vitanov

A zero-area pulse produces no excitation in a two-state quantum system on exact resonance. We show analytically and numerically that off resonance the transition probability may acquire significant values, and as the Rabi frequency increases, it approaches steadily unity, a feature reminiscent of adiabatic passage. The nature of the transition is not, however, of adiabatic nature. We show that complete population transfer occurs as a result of a quasiresonant transition between the adiabatic states due to a $\ensuremath{\delta}$-function-type interaction with an area of $\ensuremath{\pi}$.

Klaas Bergmann, Bruce W. Shore

Jaakko Lehto, Kalle‐Antti Suominen

We study the coherent dynamics of a two-level parabolic model and ways to enhance population transfer and even to obtain complete population inversion in such models. Motivated by the complete population inversion effect of zero-area pulses found in [Phys. Rev. A 73, 023416 (2006)], we consider a scheme where a given coupling function is transformed to a zero-area coupling by performing a phase jump in the middle of the evolution. With a phase-jump coupling, complete population inversion can be achieved with relatively small coupling. In the case of Zener tunneling, complete population inversion is obtained for strong-enough coupling regardless of the height of the tunneling barrier. We also derive a universal formula for the effect of the phase jump.

F. T. Hioe, C. E. Carroll