Surface Acoustic Wave Paramagnetic Resonance in Iron Doped-LiNbO 3

We studied surface acoustic wave-acoustic paramagnetic resonance (SAW-APR) of Fe2+ doped LiNbO3. Firstly, we theoretically calculated the parameters of spin Hamiltonian. From these calculations, we found that the trigonal axial field splits the triplet of lower orbital energy level in a cubic octahedral field into a singlet and a doublet. We also calculated spin-lattice coupling coefficient G(ij) and, finally, measured the temperature dependency of a SAW-APR spectrum of LiNbO3:Fe2+. We were able to observe an absorption line at about 20 K as predicted from theoretical considerations.