The purpose of this work is to investigate the material and device properties of GST-based PCM by studying relaxation oscillations [1, 2]. Our experimental results relate oscillation characteristics to applied voltage, load resistance and device thickness.
We survey progress in the PCM field over the past five years, ranging from large-scale PCM demonstrations to materials improvements for high–temperature retention and faster switching. Both materials and new cell designs that support lower-power switching are discussed, as well as higher reliability for long cycling endurance. Two paths towards higher density are discussed: through 3D integration by the combination of PCM and 3D-capable access devices, and through multiple bits per cell, by understanding and managing resistance drift caused by structural relaxation of the amorphous phase. We also briefly survey work in the nascent field of brain-inspired neuromorphic systems that use PCM to implement non-Von Neumann computing.
Perfect Quantum Cloning Machines (QCM) would allow to use quantum nonlocality for arbitrary fast signaling. However perfect QCM cannot exist. We derive a bound on the fidelity of QCM compatible with the no-signaling constraint. This bound equals the fidelity of the Bu\v{z}ek-Hillery QCM.