Method and device for providing decorrelated skyrmions

Abstract

Method for providing decorrelated skyrmions (S), comprising irradiating a decorrelation region (10) of a ferro-, ferri- or antiferromagnetic thin-film system (20) suitable for the optically induced formation of skyrmions and having a perpendicular or nearly perpendicular magnetic anisotropy with a laser pulse (P) to form skyrmions (S), characterized in that the fluence Φ of the laser pulse (P) in the decorrelation region (10) has a temperature T above a critical temperature T krit for a magnetic order of the thin-film system (20) but below a destruction threshold temperature T ZS of the thin-film system (20) for decorrelating skyrmions (S) of a previously existing skyrmion arrangement (S1), wherein above the critical temperature T kritthe mean spatial correlation of the skyrmions (S) disappears and a newly generated skyrmion arrangement (S2) by irradiation is not dependent on the previously existing skyrmion arrangement (S1).

Description

[0001] The present invention relates to a method and a device for providing decorrelated magnetic skyrmions. Furthermore, the use of such decorrelated skyrmions for stochastic data processing is proposed. State of the art

[0002] Magnetic skyrmions are magnetic quasiparticles with typical sizes in the nanometer or micrometer range, which can occur particularly in thin films as well as at surfaces and interfaces of certain magnetic systems. The generation of skyrmions and their potential practical applications represent a relatively new and active field of research. The first direct detections of such soliton vortices in magnetic fields were achieved towards the end of the previous decade. It was not until 2013 that it was demonstrated that skyrmions can be deliberately generated and quenched on surfaces (Romming et al., Sci. 341, 6146 (2013)).

[0003] Skyrmions can be observed especially in ferromagnetic multilayer systems with single femtosecond infrared laser pulses above a material-dependent fluence threshold Φ skcreated and annihilated. From an application perspective, the optical control of skyrmions offers a path to a faster and potentially more energy-efficient new class of devices in information technology. Magnetic skyrmions have been proposed as carriers of information (the individual bit) for information technology in general because they are potentially small, can be manipulated by magnetic fields and spin-polarized electric currents, and are stable at room temperature. In particular, an application in data storage is therefore being discussed (Hanneken et al., Nat. Nanotechnol. 10, 1039 (2015)). Skyrmions can potentially be used to display digital information, but also for so-called probabilistic or stochastic data processing.

[0004] In contrast to arithmetic (e.g., binary) computing, probabilistic or stochastic computing performs computational operations based on probabilities. Numbers are represented by bit sequences that contain bits with the value "1" with a certain probability. The longer the bit sequence, the more precisely the probability can be encoded and the more accurate the computations. The bit sequences can be processed by arithmetic units with low complexity. The main advantage of stochastic computing is its inherent fault tolerance, e.g., against individual bit flip errors. However, possible correlations between the bit sequences lead to computational errors, requiring the use of decorrelation units (also called reshufflers or decorrelators), which randomize the bit sequence while maintaining the probability value.

[0005] Stochastic bit sequences can be represented by sequences of skyrmions. In stochastic data processing with skyrmions, for example, information is also encoded as probabilities in bit sequences of zeros and ones, where the ones can be represented by individual skyrmions, and zeros by their absence. For correct processing, these bit sequences must exhibit no correlations, i.e., the ones and zeros of the bit sequences must be distributed completely randomly. A corresponding decorrelator should allow a bit sequence to be randomly rearranged without significantly changing the number of zeros and ones occurring in the bit sequence.

[0006] The basic concept of a skyrmion decorrelator was already filed for patent in 2016 (FR 3 051 573). One possible realization for such a decorrelator is based on the thermal diffusion of micrometer-sized skyrmions on timescales of seconds, which, however, makes its application for data processing unlikely (Zäzvorka et al., Nat. Nanotechnol. 14, 658 (2019)). Building on this, a numerical application has been suggested for calculating a result from decorrelated skyrmion sequences (Zhang et al., Phys. Rev. Applied 13, 054049 (2020)). The concept of a purely thermal decorrelator has also been proposed for the generation of truly random numbers (Yao et al., IEEE Trans. Electron Devices 67, 6 (2020)). Skyrmions are therefore in principle suitable for stochastic data processing, but the current concepts do not meet the necessary requirements for the required time and length scales.

[0007] The generation of magnetic skyrmion bubble lattices using ultrafast lasers in ultrathin films is state-of-the-art (Je et al., Nano Lett. 18, 11 (2018)). Another study deals with the formation of transient domain-wall skyrmions after ultrafast demagnetization (Lepadatu, Phys. Rev. B 102, 094402 (2020)). An overview of the current state of skyrmion electronics can be found in the review article "Skyrmion electronics: writing, deleting, reading and processing magnetic skyrmions toward spintronic applications" (Zhang et al., J. Phys. Condens. Matter 32, 14 (2020)). Disclosure of the invention

[0008] It is therefore an object of the present invention to provide a method and a device for providing decorrelated skyrmions with improved properties with regard to the time and length scales, which avoids or at least significantly reduces the problems occurring in the prior art.

[0009] These objects are achieved according to the invention by the features of patent claims 1, 5, and 6. Advantageous embodiments of the invention are contained in the respective subclaims.

[0010] A first aspect of the invention relates to a method for providing decorrelated skyrmions, comprising irradiating a decorrelation region of a ferro-, ferri- or antiferromagnetic thin-film system having a perpendicular magnetic anisotropy suitable for the optically induced formation of skyrmions with a laser pulse to form skyrmions, wherein the fluence Φ of the laser pulse in the decorrelation region has a temperature T above a critical temperature T krit for a magnetic order of the thin film system but below a destruction threshold temperature T ZS of the thin-film system for decorrelation of skyrmions of a previously existing skyrmion arrangement, whereby above the critical temperature T krit the mean spatial correlation of the skyrmions disappears and a newly generated skyrmion arrangement by irradiation is not dependent on the previously existing skyrmion arrangement.

[0011] The process can be realized, in particular, based on the optically induced creation and annihilation of skyrmions in ferromagnetic multilayers, operating on a sub-ns timescale and nanometer length scale (Büttner et al., Nat. Mater. 20, 30 (2021)). The skyrmions are generated within the layer system by irradiating the layer system with pulsed laser radiation. While previous approaches operate very slowly in the range of seconds, the process in corresponding layer systems takes place on a timescale of less than 1 ns.

[0012] The inventors demonstrated that a random distribution of skyrmions in appropriately formed magnetic layers can be generated using a single ultrashort laser pulse. The laser fluence Φ must be high enough to overcome a material-specific threshold, at which a new, fully decorrelated random distribution is generated after each shot. This distribution is then spatially absolutely random and independent of the magnetic state of the material before laser irradiation, thus also independent of any pre-existing spatial distribution of skyrmions.

[0013] Thus, random arrangements of skyrmions can be generated in an extended region of a magnetic thin-film material with a single laser pulse, i.e., in particular, without any waiting time until complete thermal decorrelation, as in the prior art. Therefore, the method according to the invention operates on very short timescales. To enable a high number of decorrelation processes per unit time, the duration τ of the laser pulses should be as short as possible. However, since optical skyrmion generation is a direct thermal process, it is not dependent on the length of the laser pulse used. The duration τ of the laser pulse is preferably in the range between 1 fs and 1 ns.

[0014] The technical requirements for the laser unit are minimal. For the random generation of skyrmions, a certain material-specific critical laser fluence Φ krit(incident energy per area) in the decorrelation region must be exceeded to ensure a random distribution of the skyrmions. The fluence Φ of the laser pulse in a decorrelation region must, in particular, be sufficient to maintain a temperature T above a material-specific critical temperature T krit for the magnetic order of the respective thin-film system but below the destruction threshold temperature T ZS of the thin-film system. In this case, the distribution of the generated skyrmions is completely decorrelated. The critical fluence Φ krit can be determined material-dependently by a disappearance of the mean correlation of the generated skyrmions.

[0015] The critical temperature T kritis the temperature T at which the mean spatial correlation C of the skyrmions disappears. At higher temperatures T generated by the irradiation, the mean spatial correlation C of the skyrmions is then constantly at the value 0 (or, within the limits of the measurement accuracy, essentially around the value 0), so that in particular a newly generated skyrmion arrangement S2 is not dependent on a previously existing arrangement S1. The spatial correlation C of two skyrmion arrangements S1 and S2 within a range B(x,y) is defined as C=∫Bdx dy S1(x,y)S2(x,y)∫Bdx dy S12(x,y)∫Bdx dy S22(x,y).

[0016] Here S1(x,y) and S2(x,y) are functional representations of the spatial skyrmion arrangements, where if a skyrmion is present at position (x,y) then S i (x,y) = 1, but in the absence of a skyrmion, S i(x,y) = 0. The mean spatial correlation is the arithmetic mean after repeatedly determining the spatial correlation C.

[0017] The destruction threshold temperature T ZS of the thin-film system is the temperature at which the first irreversible structural changes in the material system, in the sense of optically induced damage, occur. The destruction threshold temperature T ZS of the thin-film system limits the effective operating range of the invention, but is otherwise not essential to the invention. However, reaching the critical temperature T krit necessary for the inventive process.

[0018] The reason for the decorrelation of the skyrmions is a certain minimum temperature T reached by the irradiation in the thin-film system. krit. According to the invention, the temperature T is adjusted by an optical interaction. However, the initial temperature of the thin-film system is also important. While the critical fluence Φ krit can therefore only be determined material-specifically in connection with other external parameters, the critical temperature T krit determined solely by the thin-film system. However, the generation of skyrmions requires an optical interaction with a certain minimum fluence Φ sk in advance.

[0019] In other words, the fluence Φ of the laser pulse must be at least a certain material-dependent critical fluence Φ kritexceeding which the mean correlation of the generated skyrmions disappears. Starting from a correlation value of 1 for insufficiently small fluences Φ, the mean correlation of the skyrmions shows a negative linear dependence with increasing fluence Φ up to a correlation value of 0 at the critical fluence Φ krit However, for optically induced skyrmion generation, a laser pulse with a material-dependent minimum fluence Φ sk The minimum fluence Φ sk is typically around 10 mJ / cm 2 up to 15 mJ / cm 2 . The critical fluences Φ krit for decorrelation is typically above 15 mJ / cm 2 The fluence Φ must be below the destruction threshold of the thin-film system, typically below 50 mJ / cm 2However, the exact values ​​for the individual fluence ranges as well as the optimal frequency ranges of the laser pulse are material-dependent and vary between different thin-film systems.

[0020] Suitable ferro-, ferri-, or antiferromagnetic thin-film systems are known to those skilled in the art. For the formation of skyrmions, the magnetic layer must exhibit perpendicular or nearly perpendicular magnetic anisotropy. The respective layer thicknesses should preferably be less than 100 nm. Magnetic layers with a significant Dzyaloshinskii-Moriya interaction (DMI) are technologically preferred because they form homochiral skyrmions that can be manipulated with electrical currents. Magnetic anisotropy refers to the contribution to the energy of the thin-film system, which depends on the direction of magnetization. It determines the direction of the easy magnetization axis or axes. Methods for influencing magnetic anisotropy in thin-film systems are well known to those skilled in the art.In thin-film systems with perpendicular magnetic anisotropy, the easy axis is oriented perpendicular to the film plane. Magnetization in the absence of external magnetic fields therefore occurs perpendicular (or, due to tolerances in the manufacturing of the film structures, essentially perpendicular) to the film plane. In thin-film systems with nearly perpendicular anisotropy, however, magnetization in the absence of external magnetic fields is not perpendicular to the film plane; instead, the axis of magnetization is slightly tilted relative to an axis perpendicular to the film plane (i.e., relative to the perpendicular).A thin-film system in which the direction of the easy axis of magnetization has an inclination exceeding the usual tolerances for a vertical anisotropy of preferably a maximum of 10°, more preferably a maximum of 5° and even more preferably a maximum of 1° relative to the vertical is usually referred to as a material with a nearly vertical magnetic anisotropy.

[0021] In particular, the optical skyrmion decorrelation was demonstrated on two ferromagnetic multilayer thin film systems with perpendicular magnetic anisotropy: a system with multiple repeated Co / Pt layers (total thickness: 21 nm) and a system with multiple repeated Pt / Co 60 Fe 20 B 20 / MgO layers (total thickness: 76 nm), plus antioxidant layers. In Co / Pt-based thin-film systems, the intrinsic rate for the optical generation of skyrmions is approximately 300 ps (Büttner et al., Nat. Mater. 20, 30 (2021)).

[0022] Skyrmions of virtually any size and size can be randomly generated (diameters preferably between 1 nm and 10 µm). The size of the skyrmions is determined solely by the properties of the layer system and is independent of the properties of the laser pulse used. Therefore, the method according to the invention can be used to provide skyrmion sizes (diameters) in the lower nanometer range, enabling very high integration densities (e.g., for very small feature sizes in the computing units). For example, decorrelation of skyrmions with diameters between approximately 70 nm and 150 nm was achieved with the two multilayer systems mentioned above.

[0023] Preferably, the area F of the decorrelation region is limited by the extent of the thin-film system within the layer plane or by the effectively irradiated area within the thin-film system. The decorrelation region can thus be determined either by the size of the laser pulse (laser spot or beam diameter) within an extended layer system that exceeds the size of the laser pulse or by an extent of the magnetic material itself that is reduced compared to the size of the laser pulse. In particular, lithographically produced shapes can be used, such as striplines or skyrmion reservoirs with supply and / or discharge lines for the provided skyrmions.

[0024] Preferably, the density ρ sk the skyrmions have a magnetic field strength B z a component of an external magnetic field perpendicular to the decorrelation region during irradiation. The density ρsk The density of the skyrmions, which corresponds to the probability value for stochastic calculations, can thus be precisely controlled directly via the strength of the applied external magnetic field. A linear relationship prevails. In particular, the density ρ sk above the limit of laser fluence Φ sk for the optical generation of skyrmions no longer depends on the laser fluence. For example, in the Co / Pt system mentioned above, skyrmion densities of 0.5 skyrmions per µm 2 up to about 50 skyrmions per µm 2 by varying a component B perpendicular to the decorrelation area z an external magnetic field during irradiation. The maximum achievable densities ρ sk depend on the intrinsic skyrmion size (diameter).

[0025] A second aspect of the invention relates to the use of decorrelated skyrmions provided by a method according to the invention for stochastic data processing.

[0026] A third aspect of the invention relates to a skyrmion decorrelator, comprising a ferro-, ferri-, or antiferromagnetic thin-film system suitable for the optically induced formation of skyrmions, having a perpendicular or nearly perpendicular magnetic anisotropy; and a laser for irradiating a decorrelation region of the thin-film system; wherein provision of decorrelated skyrmions in the decorrelation region is effected by means of a method according to the invention.

[0027] The decorrelator can be integrated into architectures based on so-called skyrmion racetracks. Here, the skyrmions are transported in striplines to write, read, and compute units using electric current. A laser-based decorrelation unit according to the invention can be used to generate skyrmion bit sequences with a specific probability density but a random distribution, or to randomly rearrange the distribution in an existing sequence.

[0028] In the latter case, the probability density of the skyrmions must be determined beforehand in a corresponding reading element. Deleting the old distribution is not necessary. Exposure to a laser pulse according to the invention completely deletes the old distribution and simultaneously generates a new one. Thus, a decorrelation of skyrmions with identical probability density can occur. For the purposes of stochastic data processing, skyrmions are practically indistinguishable quasiparticles; therefore, the two skyrmion configurations do not differ from each other except for the decorrelation that has occurred. The decorrelation process is thus identical to a decorrelating redistribution of the skyrmions while retaining the "original" skyrmions. A skyrmion decorrelator therefore preferably further comprises a means for reading the density ρ skof the skyrmions in the decorrelation region. In particular, optical or electrical methods for detecting the skyrmions in the decorrelation region in combination with a corresponding evaluation unit for determining the density ρ sk the skyrmions are used.

[0029] Preferably, a skyrmion decorrelator further comprises a means for introducing and controlling the magnetic field strength B z a component of an external magnetic field perpendicular to the decorrelation region. On the means for introducing and controlling the magnetic field strength B z When carrying out a process according to the invention, the density ρ sk of the skyrmions via the magnetic field strength B za component of an external magnetic field perpendicular to the decorrelation region during irradiation. In particular, for decorrelation of an existing skyrmion distribution, a previously read density ρ sk the skyrmions are reproduced.

[0030] Preferably, the decorrelation region is formed as a section of a stripline for skyrmions or as a reservoir connected to at least one stripline for skyrmions. Suitable striplines for guiding skyrmions are known to those skilled in the art. The stripline or the reservoir are provided in particular by appropriate structuring of the thin-film structure.

[0031] Preferably, the thin-film system exhibits a Dzyaloshinskii-Moriya interaction (DMI). Magnetic layers with a significant Dzyaloshinskii-Moriya interaction are technologically preferred because they form homochiral skyrmions that can be manipulated with electric currents.

[0032] Preferably, the thin-film system is a Co / Pt multilayer. A Co / Pt multilayer is an example of a suitable material system that is not a DMI material.

[0033] The described examples of decorrelation measurements on skyrmions were carried out on Ta(3.6) / Pt(3.7) / [Pt(2.7) / Co 60 Fe 20 B 20 (0.9) / MgO(1.5)] 15 / Pt(2.7) multilayers (abbreviated as Pt / CoFeB / MgO) and Ta(3) / [Co(0.6) / Pt(0.8)] 15 / Ta(2) multilayers (abbreviated as Co / Pt) were deposited (thicknesses in nm are given in parentheses). Both multilayer systems were deposited on silicon nitride membranes (thickness 700 nm and 150 nm, respectively) by magnetron sputtering. During deposition, the argon pressure was set to 2.7×10 -3 mbar for Co / Pt and 4×10 -3 mbar for Pt / CoFeB / MgO (4.7×10 -3 mbar for Pt). The Pt / CoFeB / MgO layers were patterned for current injection using lift-off electron beam lithography and focused ion beam structuring into stripes 1.5 µm to 3 µm long and 0.9 µm to 1.4 µm wide. Several samples with nominally identical compositions were prepared and investigated for their properties.

[0034] Further preferred embodiments of the invention result from the features mentioned in the subclaims.

[0035] The various embodiments of the invention mentioned in this application can be advantageously combined with one another, unless otherwise stated in the individual case. Brief description of the drawings

[0036] The invention is explained below in exemplary embodiments with reference to the accompanying drawings. They show: Fig. 1 a schematic representation of an exemplary embodiment of a skyrmion decorrelator according to the invention, Fig. 2 a schematic representation of two exemplary decorrelation areas, Fig. 3 diagrams showing the dependence of the correlation between the skyrmions on the fluence Φ, and Fig. 4 diagrams showing the dependence of density ρ sk of the skyrmions of the magnetic field strength B z a component of an external magnetic field penetrating the decorrelation region perpendicularly. Detailed description of the drawings

[0037] Fig. Figure 1 shows a schematic representation of an exemplary embodiment of a skyrmion decorrelator according to the invention. The skyrmion decorrelator shown comprises a ferro-, ferri-, or antiferromagnetic thin-film system 20 with a perpendicular magnetic anisotropy suitable for the optically induced formation of skyrmions S; and a laser 30 for irradiating a decorrelation region 10 of the thin-film system 20.

[0038] A provision of decorrelated skyrmions S in the decorrelation region 10 is carried out by means of a method according to the invention comprising irradiating the decorrelation region 10 of the thin-film system 20 with a laser pulse P to form skyrmions S, wherein the fluence Φ of the laser pulse P in the decorrelation region 10 has a temperature T above the critical temperature T kritfor the magnetic order of the thin film system 20 but below the destruction threshold temperature T ZS of the thin-film system 20. The thin-film system 20 is arranged on a substrate 22 in the illustration shown.

[0039] Furthermore, a means for introducing and controlling a magnetic field strength B z a component of an external magnetic field B penetrating the decorrelation region 10 perpendicularly. The magnetic field strength B z the component of an external magnetic field B perpendicularly penetrating the decorrelation area 10 during irradiation, the density ρ sk of the skyrmions S. The duration τ of the laser pulse P is preferably in the range between 1 fs and 1 ns.

[0040] Fig. Figure 2 shows a schematic representation of two exemplary decorrelation regions 10. The area F of the decorrelation region 10 is limited upwards by the extent of the thin-film system 20 within the layer plane E or by the area A effectively irradiated in the thin-film system 20. The decorrelation region 10 can thus be determined either by the size of the laser spot of the laser pulse P or by the shape of the magnetic layer system 10. In particular, lithographically produced shapes can be used, such as striplines 40 or skyrmion reservoirs 42 with at least one stripline 40 as supply and / or discharge lines for the skyrmions S.

[0041] Fig. Figure 3 shows diagrams of the correlation between the skyrmions as a function of the fluence Φ. A correlation of skyrmion patterns generated by laser pulses is shown (circled symbols). In particular, the average correlation of the skyrmion patterns in (a) Co / Pt and (b) Pt / CoFeB / MgO is shown as a thin-film system suitable for optically induced skyrmion generation. The data points in the lower curves (square symbols) serve as controls and show the average correlation for a sample that is magnetically saturated between two pulses. The data points in the upper curves (circled symbols) show the average of at least five binary magnetization images after successive laser pulses without intermediate saturation of the sample ((a) at -83 mT, (b) at 20 mT). Insets show corresponding summed images.

[0042] In (a) it can be seen that in the upper curve the critical temperature T krit on the thin film system Co / Pt at a critical fluence Φ krit of about 27 mJ / cm 2 is reached. At this fluence Φ, the corresponding correlation curve shows a break point, beyond which the mean correlation remains constant at 0 (within the limits of the measurement accuracy). The critical fluence Φ krit can thus be determined directly from a measured dependence of the correlation between the skyrmions on the fluence Φ due to the transition from a linear decrease to a constant zero value. This critical fluence Φ, which depends on further parameters, krit corresponds to a critical temperature T krit , which essentially represents a material property of the respective thin-film system. The minimum fluence Φ sk to produce skyrmions is approximately 13 mJ / cm 2. The spatial correlation was therefore only determined for fluences Φ above this threshold.

[0043] The evaluation results for the Pt / CoFeB / MgO thin-film system shown in (b) show a similar behavior despite the smaller number of measurement points. The upper curve (circled symbols) shows the critical temperature T krit already at a critical fluence Φ krit of just over 18 mJ / cm 2 The minimum fluence Φ sk to produce skyrmions in this example is approximately 11 mJ / cm 2 .

[0044] Fig. 4 shows diagrams of the dependence of the density ρ sk of the skyrmions S from the magnetic field strength B z a component of an external magnetic field B perpendicular to the decorrelation region 10. In particular, this is the skyrmion density ρ skafter a single laser pulse irradiation of (a) Co / Pt and (b) Pt / CoFeB / MgO. The lines represent a linear fit to the data points. List of reference symbols 10 Decorrelation area 20 thin-film system 22 Substrat 30 lasers 40 stripline 42 Reservoir S Skyrmions P laser pulse B external magnetic field A effectively irradiated area E layer level

Claims

[1] Method for providing decorrelated skyrmions (S), comprising irradiating a decorrelation region (10) of a ferro-, ferri- or antiferromagnetic thin-film system (20) suitable for the optically induced formation of skyrmions and having a perpendicular or nearly perpendicular magnetic anisotropy with a laser pulse (P) to form skyrmions (S), characterized by that the fluence Φ of the laser pulse (P) in the decorrelation region (10) has a temperature T above a critical temperature T krit for a magnetic order of the thin-film system (20) but below a destruction threshold temperature T ZS of the thin-film system (20) for decorrelating skyrmions (S) of a previously existing skyrmion arrangement (S1), wherein above the critical temperature T kritthe mean spatial correlation of the skyrmions (S) disappears and a newly generated skyrmion arrangement (S2) by irradiation is not dependent on the previously existing skyrmion arrangement (S1). [2] Method according to claim 1, wherein the area F of the decorrelation region (10) is limited upwards by the extension of the thin-film system (20) within the layer plane (E) or by the area (A) effectively irradiated in the thin-film system (20). [3] Method according to claim 1 or 2, wherein the duration τ of the laser pulse (P) is in the range between 1 fs and 1 ns. [4] Method according to one of the preceding claims, wherein the density ρ sk the skyrmions (S) have a magnetic field strength B z a component of an external magnetic field (B) perpendicularly penetrating the decorrelation region (10) is adjusted during irradiation. [5] Use of decorrelated skyrmions (S) provided by a method according to one of the preceding claims for stochastic data processing. [6] Skyrmion decorrelator, comprising: a ferro-, ferri- or antiferromagnetic thin-film system (20) suitable for the optically induced formation of skyrmions (S) with a vertical or nearly vertical magnetic anisotropy; and a laser (30) for irradiating a decorrelation region (10) of the thin-film system (20); characterized by , that a provision of decorrelated skyrmions (S) in the decorrelation region (10) is carried out by means of a method according to one of claims 1 to 4. [7] Skyrmion decorrelator according to claim 6, further comprising: a means for introducing and controlling a magnetic field strength B za component of an external magnetic field (B) perpendicularly penetrating the decorrelation region (10). [8] Skyrmion decorrelator according to claim 6 or 7, wherein the decorrelation region (10) is formed as a section of a stripline (40) for skyrmions (S) or as a reservoir (42) connected to at least one stripline (40) for skyrmions (S). [9] Skyrmion decorrelator according to one of claims 6 to 8, wherein the thin film system (20) has a Dzyaloshinskii-Moriya interaction or the thin film system (20) is a Co / Pt multilayer. [10] Skyrmion decorrelator according to one of claims 7 to 9, further comprising a means for reading the density ρ sk of the skyrmions (S) in the decorrelation region (10).

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