Control of Magnetic and Topological Orders with a DC Electric Field

In this talk, we present our theoretical proposal which provides a new route to control magnetic and topological orders in a broad class of insulating magnets with a DC electric field [1]. We show from the strong-coupling expansion that magnetic exchange interactions along the electric-field direction are generally enhanced in Mott insulators. It indicates that we can control the spatial structure of the interactions in magnets with a DC electric field. To illustrate this idea, we particularly focus on two kinds of magnets, frustrated magnets and quasi-one-dimensional magnets, and obtain phase diagrams including several magnetic or topological ordered phases such as quantum spin liquids and Haldane-gap states. Our proposal is effective especially for magnets in the vicinity of quantum critical points, and would also be applicable for magnets under low-frequency AC electric fields such as terahertz laser pulses. Our result would pave a promising way to control the exotic states of matter in magnets.

[1] K. Takasan and M. Sato, arXiv:1802.04311.