Echo Trains in Pulsed Electron Spin Resonance of a Strongly Coupled Spin Ensemble.

We report on a novel dynamical phenomenon in electron spin resonance experiments of phosphorus donors. When strongly coupling the paramagnetic ensemble to a superconducting lumped element resonator, the coherent exchange between these two subsystems leads to a train of periodic, self-stimulated echoes after a conventional Hahn echo pulse sequence. The presence of these multiecho signatures is explained using a simple model based on spins rotating on the Bloch sphere, backed up by numerical calculations using the inhomogeneous Tavis-Cummings Hamiltonian.

Linearly polarized GHz magnetization dynamics of spin helix modes in the ferrimagnetic insulator CuOSeO.

Linear dichroism - the polarization dependent absorption of electromagnetic waves- is routinely exploited in applications as diverse as structure determination of DNA or polarization filters in optical technologies. Here filamentary absorbers with a large length-to-width ratio are a prerequisite. For magnetization dynamics in the few GHz frequency regime strictly linear dichroism was not observed for more than eight decades.

Through modulation of cardiac Ca handling, UCP2 affects cardiac electrophysiology and influences the susceptibility for Ca -mediated arrhythmias.

What is the central question of this study? Knockdown of UCP2 reduces mitochondrial Ca uptake. This suggests that Ucp2 knockout mice need to have additional effects on cytosolic Ca handling to prevent Ca overload. However, the specific mechanisms and their impact on cardiac electrophysiology remain speculative.