Simple Non-Markovian Microscopic Models for the Depolarizing Channel of a Single Qubit

The archetypal one-qubit noisy channels ---depolarizing, phase-damping and amplitude-damping channels--- describe both Markovian and non-Markovian evolution. Simple microscopic models for the depolarizing channel, both classical and quantum, are considered. Microscopic models which describe phase damping and amplitude damping channels are briefly reviewed.Comment: 13 pages, 2 figures. Title corrected. Paper rewritten. Added references. Some typos and errors corrected. Author adde

Coherence stabilization of a two-qubit gate by AC fields

We consider a CNOT gate operation under the influence of quantum bit-flip noise and demonstrate that ac fields can change bit-flip noise into phase noise and thereby improve coherence up to several orders of magnitude while the gate operation time remains unchanged. Within a high-frequency approximation, both purity and fidelity of the gate operation are studied analytically. The numerical treatment with a Bloch-Redfield master equation confirms the analytical results.Comment: 4 pages, 2 figure

Female Labor Force Participation in Latin America: Patterns and Explanations

Female labor force participation has increased 10 percentage points between 1990 and 2010. This paper analyzes the possible determinants of this increase. Among those determinants are changes in education, family structure, fertility, as well as changes in socioeconomic environment including wages, returns to working at home, preferences, and technology, among others. We discuss the mechanisms behind those determinants by organizing the very large theoretical and empirical literature on the subject. We then assess the relative importance of the determinants in two ways. We compute treatment effects estimated in the literature and combine them with information about the changes in the causing variables. We also use data from household surveys and combine them with a dataset of determinants to find correlations in the data that reinforce or reject the analysis of the literature review.Facultad de Ciencias Económica