Infrared phonon anomaly and magnetic excitations in single-crystal Cu3Bi(SeO3)2O2Cl

Complementary techniques for probing terahertz magnetic excitations in Cu3Bi(SeO3)2O2Cl

A low frequency magnetic excitation in Cu3Bi(SeO 3)2O2Cl has been studied through complementary spectroscopic techniques which utilised terahertz radiation from a synchrotron, a mercury arc lamp, and a two-colour photomixing system. The excitation has been studied at temperatures down to 5K and in magnetic fields up to 10T. © 2012 IEEE.

Electron spin resonance insight into broadband absorption of the Cu3Bi(SeO3)2O2Br metamagnet

Optical properties of ZnCr 2 Se 4 Spin - phonon coupling and electronic d - d - like excitations

We studied the optical properties of antiferromagnetic ZnCr2Se4 by infrared spectroscopy up to 28,000 cm −1 and for temperatures from 5 to 295 K. At the magnetic phase transition at 21 K, one of the four phonon modes reveals a clear splitting of 3 cm −1 as a result of spin-phonon coupling, the other three optical eigenmodes only show shifts of the eigenfrequencies. The antiferromagnetic orderin...

Theory of the zero-bias anomaly in magnetic tunnel junctions: Inelastic tunneling via impurities

Using the closed-time path-integral approach, we nonperturbatively study inelastic tunneling of electrons via magnetic impurities in the barrier accompanied by phonon emission in a magnetic tunnel junction. The spectrum density of phonon emission is found to show a power-law infrared singularity ,v−s1−gd with g the dimensionless electron-phonon coupling. As a consequence, the tunneling conducta...

Infrared studies of a La0.67Ca0.33MnO3 single crystal: Optical magnetoconductivity in a half-metallic ferromagnet

The infrared reflectivity of a La0.67Ca0.33MnO3 single crystal is studied over a broad range of temperatures ~78–340 K!, magnetic fields ~0–16 T!, and wave numbers (20– 9000 cm). The optical conductivity gradually changes from a Drude-like behavior to a broad peak feature near 5000 cm in the ferromagnetic state below the Curie temperature TC5307 K. Various features of the optical conductivity b...