Magnetism at the edge

Seminar
Condensed Matter Resnick seminar
QUEST Center event
No
Speaker
Yonathan Anahory, Hebrew University
Date
12/12/2024 - 13:30 - 12:30Add to Calendar 2024-12-12 12:30:00 2024-12-12 13:30:00 Magnetism at the edge Magnetism emerges from the electronic interactions between the neighboring atoms. In confined samples, the proportion of atoms near the surface is larger. Surface atoms have fewer neighbors and, thus, are expected to exhibit weaker magnetic correlations than the ones inside a bulk sample. In this work, we employ a magnetic imaging technique[1,2], which unveils a material, CrGeTe3, where we observe the opposite effect. In relatively thick samples (d>10 nm), we observe that only the edge of the sample remains magnetized at zero applied field[3]. We show that two nearby edges stabilize the magnetism in the region between the edges, resulting in a quasi-1D magnetic structure[4]. Such proximity effect is observed down to the zero-dimension limit (nanoisland). In such a limit, we can create an array of magnetic nanoparticles of different aspect ratio. The particle coercive field shows anomalous scaling as a function of dimensions, which we interpret as another evidence of the edge effect in CrGeTe3. [1]         D. Vasyukov, Y. Anahory, L. Embon, D. Halbertal, J. Cuppens, L. Neeman, A. Finkler, Y. Segev, Y. Myasoedov, M. L. Rappaport, M. E. Huber, E. Zeldov, Nat. Nanotechnol. 2013, 8, 639. [2]         Y. Anahory, H. R. Naren, E. O. Lachman, S. Buhbut Sinai, A. Uri, L. Embon, E. Yaakobi, Y. Myasoedov, M. E. Huber, R. Klajn, E. Zeldov, Nanoscale 2020, 12, 3174. [3]         A. Noah, H. Alpern, S. Singh, A. Gutfreund, G. Zisman, T. D. Feld, A. Vakahi, S. Remennik, Y. Paltiel, M. E. Huber, V. Barrena, H. Suderow, H. Steinberg, O. Millo, Y. Anahory, Nano Lett. 2022, 22, 3165. [4]         A. Noah, Y. Zur, N. Fridman, S. Singh, A. Gutfreund, E. Herrera, A. Vakahi, S. Remennik, M. E. Huber, S. Gazit, H. Suderow, H. Steinberg, O. Millo, Y. Anahory, ACS Appl. Nano Mater. 2023, 6, 8627. Conference room on the 0th floor of Resnick building Department of Physics physics.dept@mail.biu.ac.il Asia/Jerusalem public
Place
Conference room on the 0th floor of Resnick building
Abstract

Magnetism emerges from the electronic interactions between the neighboring atoms. In confined samples, the proportion of atoms near the surface is larger. Surface atoms have fewer neighbors and, thus, are expected to exhibit weaker magnetic correlations than the ones inside a bulk sample. In this work, we employ a magnetic imaging technique[1,2], which unveils a material, CrGeTe3, where we observe the opposite effect. In relatively thick samples (d>10 nm), we observe that only the edge of the sample remains magnetized at zero applied field[3]. We show that two nearby edges stabilize the magnetism in the region between the edges, resulting in a quasi-1D magnetic structure[4]. Such proximity effect is observed down to the zero-dimension limit (nanoisland). In such a limit, we can create an array of magnetic nanoparticles of different aspect ratio. The particle coercive field shows anomalous scaling as a function of dimensions, which we interpret as another evidence of the edge effect in CrGeTe3.

[1]         D. Vasyukov, Y. Anahory, L. Embon, D. Halbertal, J. Cuppens, L. Neeman, A. Finkler, Y. Segev, Y. Myasoedov, M. L. Rappaport, M. E. Huber, E. Zeldov, Nat. Nanotechnol. 2013, 8, 639.

[2]         Y. Anahory, H. R. Naren, E. O. Lachman, S. Buhbut Sinai, A. Uri, L. Embon, E. Yaakobi, Y. Myasoedov, M. E. Huber, R. Klajn, E. Zeldov, Nanoscale 2020, 12, 3174.

[3]         A. Noah, H. Alpern, S. Singh, A. Gutfreund, G. Zisman, T. D. Feld, A. Vakahi, S. Remennik, Y. Paltiel, M. E. Huber, V. Barrena, H. Suderow, H. Steinberg, O. Millo, Y. Anahory, Nano Lett. 2022, 22, 3165.

[4]         A. Noah, Y. Zur, N. Fridman, S. Singh, A. Gutfreund, E. Herrera, A. Vakahi, S. Remennik, M. E. Huber, S. Gazit, H. Suderow, H. Steinberg, O. Millo, Y. Anahory, ACS Appl. Nano Mater. 2023, 6, 8627.

Last Updated Date : 09/12/2024