Skip to Main Content
 

Global Search Box

 
 
 
 

Files

File List


thesis.pdf (66.34 MB)

ETD Abstract Container

Abstract Header

Terahertz Time Domain Spectroscopy Techniques for Antiferromagnets and Metamaterials

Heligman, Daniel Michael
http://orcid.org/0000-0002-1307-5023
http://rave.ohiolink.edu/etdc/view?acc_num=osu163784000874002

Abstract Details

2021, Doctor of Philosophy, Ohio State University, Physics.
Time domain terahertz spectroscopy has allowed for a new way to analyze the properties of antiferromagnets. Since many materials have been explored using this technique, we took a different route for evaluating their properties. We evaluated how two different antiferromagnets (CaFe2O4 and TbMn2O5) interacted with metamaterials. CaFe2O4 was coupled to split ring resonators and TbMn2O5 was coupled to gammadion crosses. From the experiment performed on the CaFe2O4/split ring resonator sample, we did not find sufficient evidence indicating coupling between the sample and the metamaterial. For the TbMn2O5/gammadion sample, we observed an improvement in the efficiency of the electromagnon excitation compared to the bare sample. To understand why the expected anticrossing, an effect observed in coupled oscillator systems, was absent from either measurement, coupling effects between split ring resonators and a hypothetical antiferromagnet were analyzed more deeply utilizing numerical methods. From here we found that an anticrossing will occur when the spins in the crystal are parallel with the interface of the sample. This would allow for improved coupling between the magnetic moment of the split ring resonators and the antiferromagnet. From the data we were able to confirm the presence of an anticrossing. Following the metamaterial project, we began the development of an additional time domain terahertz technique, on chip terahertz, which allowed us to perform measurements on antiferromagnets that were not easily probed. This technique was applied to two different antiferromagnets, CaFe2O4 and MnPS3. For CaFe2O4, we observed a possible absorption in the spectrum that could be connected to on the magnon modes. For MnPS3, we detected three possible modes, one of which could be a low frequency magnon.
Rolando Valdes Aguilar (Advisor)
Marc Bockrath (Committee Member)
Ilya Gruzberg (Committee Member)
Louis DiMauro (Committee Member)
210 p.
Condensed Matter Physics; Physics
Terahertz, Antiferromagnets, Magnon, Metamaterial, Split ring resonator

Recommended Citations

Citations

  • Heligman, D. M. (2021). Terahertz Time Domain Spectroscopy Techniques for Antiferromagnets and Metamaterials [Doctoral dissertation, Ohio State University]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=osu163784000874002

    APA Style (7th edition)

  • Heligman, Daniel. Terahertz Time Domain Spectroscopy Techniques for Antiferromagnets and Metamaterials. 2021. Ohio State University, Doctoral dissertation. OhioLINK Electronic Theses and Dissertations Center, http://rave.ohiolink.edu/etdc/view?acc_num=osu163784000874002.

    MLA Style (8th edition)

  • Heligman, Daniel. "Terahertz Time Domain Spectroscopy Techniques for Antiferromagnets and Metamaterials." Doctoral dissertation, Ohio State University, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu163784000874002

    Chicago Manual of Style (17th edition)

osu163784000874002
211
© 2021, all rights reserved.
This open access ETD is published by The Ohio State University and OhioLINK.