Electrical manipulation of skyrmions in a chiral magnet

Abstract

Writing, erasing and computing are three fundamental operations required by any working electronic device. Magnetic skyrmions could be essential bits in promising in emerging topological spintronic devices. In particular, skyrmions in chiral magnets have outstanding properties like compact texture, uniform size, and high mobility. However, creating, deleting, and driving isolated skyrmions, as prototypes of aforementioned basic operations, have been a grand challenge in chiral magnets ever since the discovery of skyrmions, and achieving all these three operations in a single device is even more challenging. Here, by engineering chiral magnet Co8Zn10Mn2 into the customized micro-devices for in-situ Lorentz transmission electron microscopy observations, we implement these three operations of skyrmions using nanosecond current pulses with a low current density of about 1010 A·m−2 at room temperature. A notched structure can create or delete magnetic skyrmions depending on the direction and magnitude of current pulses. We further show that the magnetic skyrmions can be deterministically shifted step-by-step by current pulses, allowing the establishment of the universal current-velocity relationship. These experimental results have immediate significance towards the skyrmion-based memory or logic devices.

Voltage-Controlled Skyrmionic Interconnect with Multiple Magnetic Information Carriers

“…It should be noted that the similar order of magnitude of current densities have been utilized and reported in experiments. 9 , 29 , 49 , 61 We thus believe the amplitude of current densities used in our work is safe on real thin-film-based devices.…”

“…Although multiple quasiparticles have been experimentally demonstrated in liquid crystals 7 and bulk chiral magnets, 8 , 9 it is vital to explore the conditions in which the skyrmion, skyrmionium, and antiskyrmionite may stably coexist in the same system. The coexistence of the three particles proposed in this work is outlined in the stability phase diagram, as shown in Figure 2 d. The x axis and y axis represent the DMI and PMA constants, respectively.…”

Antiferromagnetic skyrmion based shape-configured leaky-integrate-fire neuron device

“…Here, m is the unit magnetization vector in the xy lattice space. Later, the skyrmions were found at the room temperature (RT) in magnetic multilayers like Ta/CoFeB/TaOx and Pt/CoFeB/MgO and were manipulated by various means including laser [12], thermal [13], external magnetic field [14], stress [15], voltage-controlled magnetic anisotropy [16], and spin-polarized electric current [17]. Among them, the thermal gradient acts as one of the promising ways of driving the magnetic skyrmion for energy-efficient spintronic devices [18].…”

Chiral Broken Symmetry Descendants of the Kagomé Lattice Chiral Spin Liquid

“…In parallel with the interest in such CSLs, there has been a great interest in chiral broken symmetry states in geometrically frustrated systems, which can potentially display nontrivial real-space topology. The most well known examples of these are skyrmion and meron crystals -creating and manipulating such topological textures has important spintronics and information storage applications [33][34][35][36][37][38]. More recently, chiral density-wave orders have been reported in the metallic kagomé mate-rials AV 3 Sb 5 [39][40][41][42][43], prompting a search for analogous chiral magnetic orders in kagomé magnets such as FeGe [44], and giving rise to the nascent field of "chiraltronics".…”