Electric-field-driven non-volatile multi-state switching of individual skyrmions in a multiferroic heterostructure

Electrical manipulation of skyrmions attracts considerable attention for its rich physics and promising applications. To date, such a manipulation is realized mainly via spin-polarized current based on spin-transfer torque or spin–orbital torque effect.*

However, this scheme is energy consuming and may produce massive Joule heating. To reduce energy dissipation and risk of heightened temperatures of skyrmion-based devices, an effective solution is to use electric field instead of current as stimulus.*

In the article “Electric-field-driven non-volatile multi-state switching of individual skyrmions in a multiferroic heterostructure”, Yadong Wang, Lei Wang, Jing Xia, Zhengxun Lai, Guo Tian, Xichao Zhang, Zhipeng Hou, Xingsen Gao, Wenbo Mi, Chun Feng, Min Zeng, Guofu Zhou, Guanghua Yu, Guangheng Wu, Yan Zhou, Wenhong Wang, Xi-xiang Zhang and Junming Liu realize an electric-field manipulation of skyrmions in a nanostructured ferromagnetic/ferroelectrical heterostructure at room temperature via an inverse magneto-mechanical effect.*

Intriguingly, such a manipulation is non-volatile and exhibits a multistate feature. Numerical simulations indicate that the electric-field manipulation of skyrmions originates from strain-mediated modification of effective magnetic anisotropy and Dzyaloshinskii–Moriya interaction.*

The results presented in the article open a direction for constructing low-energy-dissipation, non-volatile, and multistate skyrmion-based spintronic devices.*

To minimize the influence of the magnetic field from the MFM tip on the magnetic domain structure during the magnetic force microscopy ( MFM ) measurements, NANOSENSORS™ PPP-LM-MFMR low moment magnetic AFM probes were used.*

These MFM probes are designed for magnetic force microscopy with reduced disturbance of the magnetic sample by the tip and enhanced lateral resolution compared to the standard PPP-MFMR probe. The distance between the tip and sample was maintained at a constant distance of 30 nm.*

Figure 2 from “Electric-field-driven non-volatile multi-state switching of individual skyrmions in a multiferroic heterostructure” by Yadong Wang et al.:
Electric-field-induced switching of individual skyrmion.
The transferred average strain εave and corresponding magnetic domain evolution processes in the d ~ 350 nm a [Pt/Co/Ta]12 and b [Pt/Co/Ta]8 nano-dots in a cycle of E ranging from +10 to −10 kV cm−1. Positive εave (red dots) represents tensile strain while negative εave (blue dots) represents compressive strain. μ0H represents the external magnetic field except that from the MFM tip and here μ0H is equal to be 0 mT. The inset of b illustrates the spin texture of the magnetic domain that is encompassed by the red box. The stripe domain enclosed by the black box shows the initial state of the magnetic domain evolution path. The gray dots represent the corresponding electric field for the MFM images. The MFM contrast represents the MFM tip resonant frequency shift (Δf). The scale bar represents 250 nm.

NANOSENSORS™ PPP-LM-MFMR low moment magnetic AFM probes were used
Figure 2 from “Electric-field-driven non-volatile multi-state switching of individual skyrmions in a multiferroic heterostructure” by Yadong Wang et al.:
Electric-field-induced switching of individual skyrmion.
The transferred average strain εave and corresponding magnetic domain evolution processes in the d ~ 350 nm a [Pt/Co/Ta]12 and b [Pt/Co/Ta]8 nano-dots in a cycle of E ranging from +10 to −10 kV cm−1. Positive εave (red dots) represents tensile strain while negative εave (blue dots) represents compressive strain. μ0H represents the external magnetic field except that from the MFM tip and here μ0H is equal to be 0 mT. The inset of b illustrates the spin texture of the magnetic domain that is encompassed by the red box. The stripe domain enclosed by the black box shows the initial state of the magnetic domain evolution path. The gray dots represent the corresponding electric field for the MFM images. The MFM contrast represents the MFM tip resonant frequency shift (Δf). The scale bar represents 250 nm.

*Yadong Wang, Lei Wang, Jing Xia, Zhengxun Lai, Guo Tian, Xichao Zhang, Zhipeng Hou, Xingsen Gao, Wenbo Mi, Chun Feng, Min Zeng, Guofu Zhou, Guanghua Yu, Guangheng Wu, Yan Zhou, Wenhong Wang, Xi-xiang Zhang and Junming Liu
Electric-field-driven non-volatile multi-state switching of individual skyrmions in a multiferroic heterostructure
Nature Communications volume 11, Article no. 3577 (2020)
DOI: https://doi.org/10.1038/s41467-020-17354-7

Please follow this external link to read the full article: https://rdcu.be/b6qpr

Open Access: The article “Electric-field-driven non-volatile multi-state switching of individual skyrmions in a multiferroic heterostructure” by Yadong Wang, Lei Wang, Jing Xia, Zhengxun Lai, Guo Tian, Xichao Zhang, Zhipeng Hou, Xingsen Gao, Wenbo Mi, Chun Feng, Min Zeng, Guofu Zhou, Guanghua Yu, Guangheng Wu, Yan Zhou, Wenhong Wang, Xi-xiang Zhang and Junming Liu is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.

Insights into dynamic sliding contacts from conductive atomic force microscopy

Friction in nanoscale contacts is determined by the size and structure of the interface that is hidden between the contacting bodies. One approach to investigating the origins of friction is to measure electrical conductivity as a proxy for contact size and structure. However, the relationships between contact, friction and conductivity are not fully understood, limiting the usefulness of such measurements for interpreting dynamic sliding properties.*

In their study “Insights into dynamic sliding contacts from conductive atomic force microscopy” Nicholas Chan, Mohammad R. Vazirisereshk, Ashlie Martini and Philip Egberts used atomic force microscopy (AFM) to simultaneously acquire lattice resolution images of the lateral force and current flow through the tip–sample contact formed between a highly oriented pyrolytic graphite (HOPG) sample and a conductive diamond AFM probe to explore the underlying mechanisms and correlations between friction and conductivity. Both current and lateral force exhibited fluctuations corresponding to the periodicity of the HOPG lattice.

Unexpectedly, while lateral force increased during stick events of atomic stick-slip, the current decreased exponentially.*

The results presented in the study by Nicholas Chan et al. confirm that the correlation between conduction and atom–atom distance previously proposed for stationary contacts can be extended to sliding contacts in the stick-slip regime.*

A NANOSENSORS™ conductive diamond coated AFM probe CDT-CONTR was used to obtain all experimental data presented in their manuscript.*

Figure 1 (a) from “Insights into dynamic sliding contacts from conductive atomic force microscopy” by Nicholas Chan et al:
A schematic of the experimental setup is shown in Fig. 1(a). The experiment was conducted using an ultra-high vacuum (UHV) (RHK) AFM at room temperature at a pressure of <1109Torr. A doped diamond coated cantilever (NANOSENSORS CDT-CONTR) with a normal bending spring constant of 0.86 N m1and lateral spring constant of 10 N m1was used to obtain all experimental data presented in this manuscript.

Figure 1 (a) from “Insights into dynamic sliding contacts from conductive atomic force microscopy” by Nicholas Chan et al:
A schematic of the experimental setup is shown in Fig. 1(a). The experiment was conducted using an ultra-high vacuum (UHV)AFM at room temperature at a pressure of <1109Torr. A doped diamond coated cantilever (NANOSENSORS CDT-CONTR) with a normal bending spring constant of 0.86 N m1and lateral spring constant of 10 N m1was used to obtain all experimental data presented in this manuscript.

*Nicholas Chan, Mohammad R. Vazirisereshk, Ashlie Martini and Philip Egberts
Insights into dynamic sliding contacts from conductive atomic force microscopy
Nanoscale Advances., 2020, Advance Article
DOI: 10.1039/d0na00414f

Please follow this external link to read the whole article: https://pubs.rsc.org/en/content/articlepdf/2020/na/d0na00414f

Open Access: The article “Insights into dynamic sliding contacts from conductive atomic force microscopy” by Nicholas Chan, Mohammad R. Vazirisereshk, Ashlie Martini and Philip Egberts is licensed under a Creative Commons Attribution 3.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/3.0/.

Video on NANOSENSORS™ Membrane-type Surface-stress Sensors (MSS) for olfactory sensing passes 1500 views mark

The video on NANOSENSORS™ Membrane-type Surface-stress Sensors (MSS) for olfactory sensing has passed the 1500 views mark. Thank you all for watching.

Video: What are NANOSENSORS Membrane-type Surface-stress Sensors (MSS) for R&D in gas/odor sensing?

The NANOSENSORS™ Membrane-type Surface-stress Sensor – MSS is a non-packaged MEMS sensor, a silicon membrane platform supported with four beams on which piezoresistors are embedded. It is mainly dedicated to R&D in the areas of olfactory sensing and electronic noses.

There are currently two major applications for this type of sensor:

  • the MSS has a great potential as a core component for electronic (artificial) nose systems / olfactory sensing systems utilized in e.g., medical, food, environment, safety and security fields.
  • the MSS can also be used for assessment of various materials like organic conductors, magnetic and superconductor materials in torque magnetometry.

To find out more please have a look at the video or at the NANOSENSORS™ MSS webpage or the NANOSENSORS™Special Developments List. On these pages you will not only get more information on which types of MSS Sensors are currently available but you will also find further information on the NANOSENSORS™ MSS 8 Channel Readout Module ( MSS-8RM ). The MSS-8RM is a basic electronic module to operate and to readout NANOSENSORS™ MSS that can be integrated in the researchers own set-up.