Funding source: Exploratory Research Projects - PN-III-P4-IDPCE-2016

 

Project code: PN-III-P4-ID-PCE-2016-0358

 

Contract number: 149/2017

 

Project duration: July 2017 - December 2019

 

Total budget: RON 850,000

 

Project summary:
 

The aim of this project is to explore the development of near-lossless domain wall nano-conduits using cylindrical magnetic nanowires and submicron wires in order to reach record-breaking domain wall velocities and mobilities for domain wall logic applications. This envisages both an understanding of the role of wire cross section geometry (circular vs. rectangular in the case of the state-of-the-art planar nanowires) in domain wall mobility and of the wires’ magnetic domain structure on its domain wall velocity and mobility. Why is this important? Since typical magnetic wires prepared by rapid solidification usually exhibit a core-shell type magnetic structure, and, depending on the magnetization of the shell, it may enhance or obstruct the propagation of the domain wall within the core. On the other hand, going to sufficiently small values with the wire diameter may result in a single-domain magnetic structure, which could drastically alter the domain wall mobility and velocity. This also depends on the overall magnetic anisotropy within the wire. Therefore, the structural characteristics of the wires are also an essential factor (e.g., amorphous vs. nanocrystalline). All these aspects have to be carefully and comprehensively investigated in order to control and diminish any potential losses and enhance the domain wall propagation characteristics (mobility, velocity) as much as possible for increased device speed in magnetic logic applications. The use of the near-lossless cylindrical nanowires/submicron wires as domain wall conduits for magnetic logic applications would result in a completely novel and different way of processing the information, characterized by enhanced data speeds, along with reduced power consumption. Magnetic logic has even more advantages over conventional electronic logic, given that it uses no transistors, and therefore, it exhibits very little heating caused by data switching.

 

Project team:
 

The research team consists of the Project Director - Dr. Tibor-Adrian Óvári, five experienced Senior Scientists - Prof. Dr. Horia Chiriac, Dr. Nicoleta Lupu, Dr. Firuța Borza, Dr. Sorin Corodeanu and Dr. Mihai Țibu, one postdoctoral researcher - Dr. Cristian Rotărescu, and one PhD student - Mr. Costică Hlenschi.

 

Expected results:
 

• 4 deliverables (D1 - D4), according to the initial project proposal, which will include both experimental and calculated data with reference to: D1 - role of sample geometry on the mobility of magnetic domain walls; D2 - effect of magnetic domain structure and anisotropy on the domain wall velocity and mobility in cylindrical magnetic nanowires and submicron wires; D3 - influence of structural characteristics and structural relaxation on the domain wall mobility in amorphous and nanocrystalline submicron wires and nanowires; and D4 - achievement of near-lossless magnetic domain wall nano-conduits based on rapidly solidified magnetic nanowires/submicron wires.

 

Other estimated results:
 

• Publications in the most prestigious scientific journals on the topic of this project (Magnetism and magnetic materials), e.g.: IEEE Transactions on Magnetics, IEEE Magnetics Letters, Journal of Magnetism and Magnetic Materials, as well as in journals focused on close topics, e.g. Journal of Applied Physics, AIP Advances, etc.

• Presentation of the project results at well-known international conferences on the topics of the project, e.g. MMM 2017 - Annual Conference on Magnetism and Magnetic Materials, 2018 Intermag Conference, Joint MMM-Intermag Conference 2019, etc.;

• Updated project website;

• One PhD thesis on the topic of the project (Mr. C. Hlenschi);

• Training of the postdoctoral researcher from the project team (Dr. C. Rotărescu).

 

2019 Interim Report  (in Romanian) on the project progress between July 12, 2017 and September 29, 2019
2018 Activity report (in Romanian) - Report on the effect of magnetic anisotropy on the domain wall mobility in cylindrical amorphous nanowire and submicron wire samples and on the preparation of nanocrystalline nanowires and submicron wires for the investigation of the influence of structural characteristics on the domain wall mobility in the next stage.

2017 Activity report (in Romanian) - Report on the preparation of cylindrical amorphous nanowire and submicron wire samples with diameters from 100 to 900 nm and on the domain wall velocity measurement set-up developed in order to measure such ultra-thin samples.

 

 

 

Publications:

(1) S. Corodeanu, H. Chiriac, A. Damian, N. Lupu, T.-A. Óvári, "Field and current controlled domain wall propagation in twisted glass-coated magnetic microwires", Scientific Reports 9 (2019) 5868 - https://www.nature.com/articles/s41598-019-42352-1.pdf.
(2) C. Hlenschi, S. Corodeanu, N. Lupu, H. Chiriac, "Flexible force sensors based on permeability change in ultra-soft amorphous wires", IEEE Sensors Journal 19 (2019) 6644.
(3) C. Rotărescu, H. Chiriac, N. Lupu, T.-A. Óvári, "Angular dependence of the magnetization process in low and highly magnetostrictive amorphous glass-coated nanowires prepared by rapid quenching and drawing", Journal of Magnetism and Magnetic Materials 487 (2019) 165299.
(4) C. Rotărescu, H. Chiriac, N. Lupu și T.-A. Óvári, „Micromagnetic analysis of magnetization reversal in Fe77.5Si7.5B15 amorphous glass-coated nanowires”, AIP Advances 9 (2019) 105316.
(5) Book chapter: "Recent trends in magnetic nanowires and submicron wires prepared by the quenching and drawing technique" – T.-A. Óvári, N. Lupu, H. Chiriac, in "Magnetic Nano- and Microwires: Design, Synthesis, Properties and Applications" – 2nd Edition, to be published: April 1, 2020 (Elsevier) - https://www.elsevier.com/books/magnetic-nano-and-microwires/vazquez/978-0-08-102832-2
(6) V. Rodionova, A. Zhukov, D. Atkinson, M. Vázquez, N. Lupu, L. Panina, R. Varga, Y. Honkura, „Magnetic wires, microwires, submicron wires and nanowires: Production, properties, applications”, Journal of Magnetism and Magnetic Materials (2019) – trimis Decembrie 2019.

 

Conference presentations:
 

(1) 62nd Annual Conference on Magnetism and Magnetic Materials - MMM 2017, Pittsburgh, U.S.A., November 6-10, 2017, AR-01: “Phenomenology of magnetic nucleation in rapidly solidified cylindrical amorphous nanowires” - T.-A. Óvári, C. Rotărescu, N. Lupu, H. Chiriac;

(2) Intermag 2018 - International Magnetics Conference - Singapore, April 23-27, CQ-09: “Domain wall configurations in amorphous ferromagnetic nanowires with cylindrical symmetry” - C. Rotărescu, H. Chiriac, N. Lupu, T.-A. Óvári;

(3) 9th Joint European Magnetic Symposia (JEMS) 2018, Mainz, Germany, September 3-7, 2018, A-1979 (P-B.122): “Elongated nano-conduits for the fast motion of vortex domain walls” - C. Rotărescu, H. Chiriac, N. Lupu, T.-A. Óvári.
(4) 12th European Magnetic Sensors and Actuators Conference EMSA 2018, Athens, Greece, July 1-4, 2018, PW-11: „Phenomenological modeling of the large Barkhausen effect in rapidly solidified amorphous nanowires” – T.-A. Óvári, C. Rotărescu, C. Hlenschi, H. Chiriac, N. Lupu.

 

Contact details:
 

Dr. Tibor-Adrian Óvári

National Institute of Research and Development for Technical Physics

47 Mangeron Boulevard, 700050 Iasi

Email: taovari [at] phys-iasi.ro

Tel: 0232-430680 ext. 241

Fax: 0232-231132