radioelectronicsИзвестия высших учебных заведений России. РадиоэлектроникаJournal of the Russian Universities. Radioelectronics1993-89852658-4794Saint Petersburg Electrotechnical University10.32603/1993-8985-2019-22-6-55-63radioelectronics-391Research ArticleКВАНТОВАЯ, ТВЕРДОТЕЛЬНАЯ, ПЛАЗМЕННАЯ И ВАКУУМНАЯ ЭЛЕКТРОНИКАQUANTUM, SOLID-STATE, PLASMA AND VACUUM ELECTRONICSDispersion Characteristics of Spin-Electromagnetic Waves in Planar Multiferroic Structures with Coplanar Transmission LineDispersion Characteristics of Spin-Electromagnetic Waves in Planar Multiferroic Structures with Coplanar Transmission Linehttps://orcid.org/0000-0001-6372-3220NikitinAleksei А.NikitinAleksei A.

Master Degree on electronic and nanoelectronic and Master of Science (Technology): Computational Engineering (2015), Assistant Professor (2019) of the Department of Physical Electronics and Technology.

5 Professor Popov Str., Saint Petersburg 197376

Master Degree on electronic and nanoelectronic and Master of Science (Technology): Computational Engineering (2015), Assistant Professor (2019) of the Department of Physical Electronics and Technology.

5 Professor Popov Str., Saint Petersburg 197376

aleksei.a.nikitin@gmail.comhttps://orcid.org/0000-0002-7382-9210UstinovAlexey B.UstinovA. B.

Dr. Sci. (Phys.-Math.) (2012), Associate Professor (2010) of the Department of Physical Electronics and Technologies.

5 Professor Popov Str., Saint Petersburg 197376

Dr. Sci. (Phys.-Math.) (2012), Associate Professor (2010) of the Department of Physical Electronics and Technologies.

5 Professor Popov Str., Saint Petersburg 197376

Ustinov_rus@yahoo.comhttps://orcid.org/0000-0002-4226-4341NikitinAndrey А.NikitinAndrey A.

Cand. Sci. (Phys.-Math.) (2011), Associate Professor (2015) of the Department of Physical Electronics and Technology.

5 Professor Popov Str., Saint Petersburg 197376

Cand. Sci. (Phys.-Math.) (2011), Associate Professor (2015) of the Department of Physical Electronics and Technology.

5 Professor Popov Str., Saint Petersburg 197376

and.a.nikitin@gmail.comhttps://orcid.org/0000-0002-1596-2849LähderantaErkkiLähderantaErkki

Doctor of Philosophy (Solid State Physics) (1993), Professor in Physics (2004).

34 Yliopistonkatu, Lappeenranta, 53850

Doctor of Philosophy (Solid State Physics) (1993), Professor in Physics (2004).

34 Yliopistonkatu, Lappeenranta, 53850

erkki.lahderanta@lut.fihttps://orcid.org/0000-0003-4968-1225KalinikosBoris А.KalinikosBoris A.

Dr. Sci. (Phys.-Math.) (1985), Distinguished Professor (2019).

Dr. Sci. (Phys.-Math.) (1985), Distinguished Professor (2019).

boris.kalinikos@gmail.comSaint Petersburg Electrotechnical University; LUT-UniversityРоссияSaint Petersburg Electrotechnical University; LUT-UniversityRussian FederationSaint Petersburg Electrotechnical UniversityРоссияSaint Petersburg Electrotechnical UniversityRussian FederationLUT-UniversityФинляндияLUT-UniversityFinland2019070120202265563Copyright © Nikitin A.А., Ustinov A.B., Nikitin A.А., Lähderanta E., Kalinikos B.А., 20202020Nikitin A.А., Ustinov A.B., Nikitin A.А., Lähderanta E., Kalinikos B.А.Nikitin A.A., Ustinov A.B., Nikitin A.A., Lähderanta E., Kalinikos B.A.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://re.eltech.ru/jour/article/view/391Introduction

Introduction. The distinctive feature of a coplanar transmission line with thin ferrite and ferroelectric films is the absence of undesirable irregularities in dispersion for relatively low frequencies when the wavelength approaches the thickness of ferroelectric layer, in contrast to the open ferrite-ferroelectric wave-guiding structure without metallization.

Aim

Aim. The purpose of this paper is twofold: (i) to develop a theory of the wave spectra in the multiferroic structures based on the coplanar lines; (ii) using this theory to find ways to enhance the electric tuning range.

Materials and methods

Materials and methods. The dispersion relation for spin-electromagnetic waves was derived through analytical solution of the full set of the Maxwell's equations utilizing a method of approximate boundary conditions.

Results

Results. A theory of spin-electromagnetic wave spectrum has been developed for the thin-film ferrite-ferroelectric structure based on a coplanar transmission line. According to this theory, dispersion characteristics of the spin-electromagnetic waves were described and analyzed for different parameters of the structure. The obtained results show that the investigated structure demonstrates a dual electric and magnetic field tunability of wave spectra. Its efficiency increases with an increase in the thicknesses of the ferrite and ferroelectric films and with a decrease in the width of the central metal strip.

Conclusion

Conclusion. The distinctive features of the proposed coplanar waveguides are the thin-film planar topology and dual tunability of the wave spectra. All these advantages make the proposed structures perspective for development of new microwave devices.

Introduction

Introduction. The distinctive feature of a coplanar transmission line with thin ferrite and ferroelectric films is the absence of undesirable irregularities in dispersion for relatively low frequencies when the wavelength approaches the thickness of ferroelectric layer, in contrast to the open ferrite-ferroelectric wave-guiding structure without metallization.

Aim

Aim. The purpose of this paper is twofold: (i) to develop a theory of the wave spectra in the multiferroic structures based on the coplanar lines; (ii) using this theory to find ways to enhance the electric tuning range.

Materials and methods

Materials and methods. The dispersion relation for spin-electromagnetic waves was derived through analytical solution of the full set of the Maxwell's equations utilizing a method of approximate boundary conditions.

Results

Results. A theory of spin-electromagnetic wave spectrum has been developed for the thin-film ferrite-ferroelectric structure based on a coplanar transmission line. According to this theory, dispersion characteristics of the spin-electromagnetic waves were described and analyzed for different parameters of the structure. The obtained results show that the investigated structure demonstrates a dual electric and magnetic field tunability of wave spectra. Its efficiency increases with an increase in the thicknesses of the ferrite and ferroelectric films and with a decrease in the width of the central metal strip.

Conclusion

Conclusion. The distinctive features of the proposed coplanar waveguides are the thin-film planar topology and dual tunability of the wave spectra. All these advantages make the proposed structures perspective for development of new microwave devices.

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The authors declare that there are no conflicts of interest present.