Realization of ordered magnetic skyrmions in thin films at ambient conditions

Abstract

Magnetic skyrmions present interesting physics due to their topological nature and hold significant promise for future information technologies. A key barrier to realizing skyrmion devices has been stabilizing these spin structures under ambient conditions. In this manuscript, we exploit the tunable magnetic properties of amorphous Fe/Gd mulitlayers to realize skyrmion lattices which are stable over a large temperature and magnetic field parameter space, including room temperature and zero magnetic field. These hybrid skyrmions have both Bloch-type and Néel-type character and are stabilized by dipolar interactions rather than Dzyaloshinskii-Moriya interactions, which are typically considered required for the generation of skyrmions. Small angle neutron scattering (SANS) was used in combination with soft X-ray microscopy to provide a unique, multi-scale probe of the local and long-range order of these structures. These results identify a pathway to engineer controllable skyrmion phases in thin film geometries which are stable at ambient conditions.

Metastable solitonic states in the strained itinerant helimagnet FeGe

“…4(a)], which unambiguously indicates an anharmonicity of the magnetic modulation. Similar higher-order scattering peaks have been previously observed in other chiral magnets [17,28,40] and centrosymmetric systems with long-periodic magnetic texture [41][42][43], and they can be applied as indicators of a spiral distortion. Therefore, the formation of a distorted helical texture, or CSL, was assisted by the magnetic field applied perpendicular to the strain in the thin plate plane, which has not been reported previously for FeGe or Cu 2 OSeO 3 .…”

Regular and in-plane skyrmions and antiskyrmions from boundary instabilities

“…Note that for an edge with vacuum, the conditions φ = const and D = 0 can be satisfied irrespective of the form of the DMI tensor, D ij , as can be seen from Eqs. ( 8) and (9). We introduce the dimensionless units for the length, e.g., x is redefined as…”

“…Magnetic skyrmions and antiskyrmions, which are topologically protected whirls of magnetic moments on the nanometer scale, have been a topic of great interest in recent years [1][2][3][4][5][6][7][8]. The Dzyaloshinskii-Moriya interaction (DMI) helps stabilize these structures, among other mechanisms such as dipole-dipole interaction [9] or the competing exchange interactions between neighbors [10,11]. The symmetry or asymmetry of interfacial DMI determines the type of structure formed [12,13].…”

“…Due to different conditions required to create stable skyrmions or antiskyrmions, methods for their generation form an important piece of skyrmion related research. There are a number of theoretical proposals [18][19][20][21][22], as well as direct experimental observations of skyrmion generation [9,[23][24][25][26][27]. It is desirable to develop universal means for generating both skyrmions and antiskyrmions.…”

Enhancement of zero-field skyrmion density in [Pt/Co/Fe/Ir]2 multilayers at room temperature by the first-order reversal curve

“…16 The first-order reversal curve (FORC) technique has been proven to be an effective method in probing the magnetization reversal mechanism. [18][19][20][21][22][23][24][25][26][27] This approach collects a larger dataset compared with the complete magnetization hysteresis (M-H) loop, from which information about the distribution of switching fields and interaction fields for all of the domains that contribute to the M-H loop and the irreversibility of magnetization switching can be derived, such as the magnetization switching process during complete reversal in Co/Pt multilayers. 28 An open question is that whether the zero-field skyrmion density can be highly improved via analyzing the process of magnetization reversal or not.…”