Dynamics of pulsed saturation in inhomogeneously broadened two-level systems

L.D. Zusman

V. S. Kuz’min

Vladimir Kuz

On the basis of Bloch's equations an analytical expression is obtained for the pulsed saturation signal of a two-level quantum system with allowance for inhomogeneous line broadening. It is shown that in this case the signal drop is exponential over the initial portion and nonexponential for long times. It is found that starting from a certain time, which depends on the field magnitude, relaxation parameters, and inhomogeneous width of the line, a through appears in the line contour, the depth and width of which increases with an increase in pulse duration. At smaller durations of the pulse, when the line is bell-shaped, an exponential decay of the signal indicates saturation of homogeneously broadened line. Comparison of the results obtained in an experiment on pulsed saturation in ruby shows that at large amplitudes of the field and considerable inhomogeneous broadening, one observes a deviation from the Bloch theory manifesting itself as a biexponential drop in the pulsed saturation signal A conclusion is drawn that the Bloch theory satisfactorily describes the experiment until the effective time of energy transfer to the lattice is smaller than the time of the spectral propagation of excitation.

Amenaida Ferrer Marcano, O. M. C. Salazar, J. L. Paz +2 more

Polarization and Rayleigh type optical mixing spectra of a homogeneously and inhomogeneously broadened two-level system are calculated. We show that the nonlinear signal has contributions from the population pulsation and saturation effect. In the homogeneous system these effects can induce an asymmetric spectrum when the probe frequency is different from the resonant value. In the inhomogeneous system the spectral response is always symmetric independent of the probe frequency value. Line saturation and dynamic stark splitting are substantially reduced in the inhomogeneous case. The mentioned differences can be used to identify the type of broadening of a given spectral line.

Давид Николаевич Клышко, Yu.S. Konstantinov, V. S. Tumanov

O. Arístides Marcano, Isaac Reif, José Luis Paz +1 more

Resonant Rayleigh-type optical mixing spectra for homogeneously and inhomogeneously broadened two-level systems are calculated. Differences in the forms of the spectra, such as symmetry, saturation and AC Stark splitting are presented. The observed differences can be used to discriminate whether the spectrum is homogeneously or inhomogeneously broadened.