The Justice Archive: Transitional Justice and Digital Memory

This article introduces the justice archive as a concept and set of practices emerging from recent developments in transitional justice, memory, and digital technology. Drawing on evidence from the Americas and the Balkans, it examines digital archiving and memory activism and considers the role of international law and regulation

Broadband sum frequency generation via chirped quasi-phase-matching

An efficient broadband sum frequency generation (SFG) technique using the two collinear optical parametric processes \omega 3=\omega 1+\omega 2 and \omega 4=\omega 1+\omega 3 is proposed. The technique uses chirped quasi-phase-matched gratings, which, in the undepleted pump approximation, make SFG analogous to adiabatic population transfer in three-state systems with crossing energies in quantum physics. If the local modulation period %for aperiodically poled quasi-phase-matching first makes the phase match occur for \omega 3 and then for \omega 4 SFG processes then the energy is converted adiabatically to the \omega 4 field. Efficient SFG of the \omega 4 field is also possible by the opposite direction of the local modulation sweep; then transient SFG of the \omega 3 field is strongly reduced. Most of these features remain valid in the nonlinear regime of depleted pump