Ultrafast terahertz transmission ellipsometry of YMn2O5 electromagnons

Abstract

Terahertz time-domain polarization measurement experiments probe the electomagnon excitations in an orthorhombic multiferroic YMn2O5. Spectral phase rotation function measured from the mutually orthogonal polarization components of transmitted probe pulses sensitively resolves the electromagnon resonances which appear unresolvable in conventional transmission spectroscopy. The retrieved oscillator parameters based on electro-optic effects in a lossy birefringent material show good agreement with the previously reported Fourier transform infrared spectroscopy data. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4772206]