Photoinduced Bidirectional Magnetism against Monodirectional Electronics in Square-Antiprismatic Octacyanometalates

Abstract

Irradiating ${\mathrm{Cu}}_2\mathrm{Mo}(\mathrm{CN}{)}_8\cdot 8{\mathrm{H}}_2\mathrm{O}$ with blue light induces a global magnetization, whereas succeeding irradiations with red or longer-wavelength light demagnetize this material. We solve the time-dependent Schrödinger equation for an extended Hubbard model to reproduce the photoreversible magnetism. Monitoring the photoinduced optical-conductivity and angle-resolved-photoemission spectra, we reveal that the magnetic round trip by way of ferromagnetism is far from a return in terms of electronics. While visible-light-induced magnetization has never been observed in the tungsten analog ${\mathrm{Cu}}_2\mathrm{W}(\mathrm{CN}{)}_8\cdot 5{\mathrm{H}}_2\mathrm{O}$, infrared-light irradiation may magnetize this material as well.

5 pages, 6 figures + Supplemental Material (5 pages, 6 figures), to be published in J. Phys. Soc. Jpn