Strong Excitation Regime Research Articles

Trapped ions in the strong-excitation regime: Ion interferometry and nonclassical states

The interaction of a trapped ion with a laser beam in the strong excitation regime is analyzed. In this regime, a variety of non--classical states of motion can be prepared either by using laser pulses of well defined area, or by an adiabatic passage scheme based on the variation of the laser frequency. We show how these states can be used to investigate fundamental properties of quantum mechanics. We also study possible applications of this system to build an ion interferometer.

Is the optical Bloch equation violated in Pr3+ : LaF3?

From measurements of various types of spin echoes of hyperfine transitions in 3H4 and photon echoes for the 1D2−3H4 transition in Pr3+:LaF3, we found that dephasings in both transitions are mainly due to the spectral diffusion. A correlated time τc of the fluctuating local fields is shown to be much longer than the usually used value of T2 = 21.7 μs. These results indicate that even in the absence of the excitation the dephasing cannot be described by the Bloch equation and therefore the anomalous power dependence of the optical FID observed by DeVoe and Brewer [Phys. Rev. Lett. 50 (1983) 1269] does not mean a violation of the optical Bloch equation in the strong excitation regime. Their results should be interpreted as a power dependence of the system whose decay is governed by the spectral diffusion. In this sense the standpoint of almost all theories proposed to explain this violation is not correct.

Analysis of dissociation processes through interferometric studies of VT relaxation times

A simple method is described for obtaining useful information on laser-induced dissociation processes of polyatomic molecules by studying VT relaxation in a regime of strong laser excitation. Our studies were carried out by using an interferometric technique. We also briefly outline a theoretical analysis of VT relaxation times in the presence of dissociation..

Interferometric studies of VT relaxation times in a regime of strong laser excitation

In this paper we describe the analysis of non-linearities in the vibrational relaxation rates of SF 6 molecules in a regime of strong laser excitation. Our studies were carried out using an interferometric technique which is particularly suitable to the investigation of the time dependence of VT relaxation times in molecular systems. At very high excitation energies a dramatic decrease in the VT relaxation time was found. This behaviour is related to the beginning of multiphoton dissociation processes of SF 6 molecules.