skip to main content
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

This content will become publicly available on October 29, 2020

Title: Topological Magnetic-Spin Textures in Two-Dimensional van der Waals Cr 2Ge 2Te 6

Abstract

Two-dimensional (2D) van der Waals (vdW) materials show a range of profound physical properties that can be tailored through their incorporation in heterostructures and manipulated with external forces. The recent discovery of long-range ferromagnetic order down to atomic layers provides an additional degree of freedom in engineering 2D materials and their heterostructure devices for spintronics, valleytronics, and magnetic tunnel junction switches. In this work, using direct imaging by cryo-Lorentz transmission electron microscopy we show that topologically nontrivial magnetic-spin states, skyrmionic bubbles, can be realized in exfoliated insulating 2D vdW Cr 2Ge 2Te 6. Due to the competition between dipolar interactions and uniaxial magnetic anisotropy, hexagonally packed nanoscale bubble lattices emerge by field cooling with magnetic field applied along the out-of-plane direction. Despite a range of topological spin textures in stripe domains arising due to pair formation and annihilation of Bloch lines, bubble lattices with single chirality are prevalent. In conclusion, our observation of topologically nontrivial homochiral skyrmionic bubbles in exfoliated vdW materials provides a new avenue for novel quantum states in atomically thin insulators for magneto-electronic and quantum devices.

Authors:
ORCiD logo [1];  [2]; ORCiD logo [1];  [3];  [1];  [4]; ORCiD logo [4]; ORCiD logo [1]; ORCiD logo [3]; ORCiD logo [2]
  1. Brookhaven National Lab. (BNL), Upton, NY (United States)
  2. Brookhaven National Lab. (BNL), Upton, NY (United States); Stony Brook Univ., NY (United States)
  3. Univ. of Pennsylvania, Philadelphia, PA (United States)
  4. NG Next, Northrop Grumman Corporation, Redondo Beach, CA (United States)
Publication Date:
Research Org.:
Brookhaven National Lab. (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Materials Sciences & Engineering Division
OSTI Identifier:
1580243
Report Number(s):
BNL-212475-2019-JAAM
Journal ID: ISSN 1530-6984
Grant/Contract Number:  
SC0012704; AC02-98CH10886
Resource Type:
Accepted Manuscript
Journal Name:
Nano Letters
Additional Journal Information:
Journal Volume: 19; Journal Issue: 11; Journal ID: ISSN 1530-6984
Publisher:
American Chemical Society
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; van der Waals; topological; two-dimensional; ferromagnetism; Skyrmions; spintronics; Lorentz microscopy; Dzyaloshinskii-Moriya

Citation Formats

Han, Myung-Geun, Garlow, Joseph A., Liu, Yu, Zhang, Huiqin, Li, Jun, DiMarzio, Donald, Knight, Mark W., Petrovic, Cedomir, Jariwala, Deep, and Zhu, Yimei. Topological Magnetic-Spin Textures in Two-Dimensional van der Waals Cr2Ge2Te6. United States: N. p., 2019. Web. doi:10.1021/acs.nanolett.9b02849.
Han, Myung-Geun, Garlow, Joseph A., Liu, Yu, Zhang, Huiqin, Li, Jun, DiMarzio, Donald, Knight, Mark W., Petrovic, Cedomir, Jariwala, Deep, & Zhu, Yimei. Topological Magnetic-Spin Textures in Two-Dimensional van der Waals Cr2Ge2Te6. United States. doi:10.1021/acs.nanolett.9b02849.
Han, Myung-Geun, Garlow, Joseph A., Liu, Yu, Zhang, Huiqin, Li, Jun, DiMarzio, Donald, Knight, Mark W., Petrovic, Cedomir, Jariwala, Deep, and Zhu, Yimei. Tue . "Topological Magnetic-Spin Textures in Two-Dimensional van der Waals Cr2Ge2Te6". United States. doi:10.1021/acs.nanolett.9b02849.
@article{osti_1580243,
title = {Topological Magnetic-Spin Textures in Two-Dimensional van der Waals Cr2Ge2Te6},
author = {Han, Myung-Geun and Garlow, Joseph A. and Liu, Yu and Zhang, Huiqin and Li, Jun and DiMarzio, Donald and Knight, Mark W. and Petrovic, Cedomir and Jariwala, Deep and Zhu, Yimei},
abstractNote = {Two-dimensional (2D) van der Waals (vdW) materials show a range of profound physical properties that can be tailored through their incorporation in heterostructures and manipulated with external forces. The recent discovery of long-range ferromagnetic order down to atomic layers provides an additional degree of freedom in engineering 2D materials and their heterostructure devices for spintronics, valleytronics, and magnetic tunnel junction switches. In this work, using direct imaging by cryo-Lorentz transmission electron microscopy we show that topologically nontrivial magnetic-spin states, skyrmionic bubbles, can be realized in exfoliated insulating 2D vdW Cr2Ge2Te6. Due to the competition between dipolar interactions and uniaxial magnetic anisotropy, hexagonally packed nanoscale bubble lattices emerge by field cooling with magnetic field applied along the out-of-plane direction. Despite a range of topological spin textures in stripe domains arising due to pair formation and annihilation of Bloch lines, bubble lattices with single chirality are prevalent. In conclusion, our observation of topologically nontrivial homochiral skyrmionic bubbles in exfoliated vdW materials provides a new avenue for novel quantum states in atomically thin insulators for magneto-electronic and quantum devices.},
doi = {10.1021/acs.nanolett.9b02849},
journal = {Nano Letters},
number = 11,
volume = 19,
place = {United States},
year = {2019},
month = {10}
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on October 29, 2020
Publisher's Version of Record

Save / Share: