Interplay between lattice and spin states degree of freedom in the FeSe superconductor: dynamic spin state instabilities

Vladimir Gnezdilov, Yurii G. Pashkevich, Peter Lemmens +5

Polarized Raman-scattering spectra of superconducting, single-crystalline FeSe evidence pronounced phonon anomalies with temperature reduction. A large 6.5% hardening of the B_1g(F…