2023 Annual Meeting of the APS Mid-Atlantic Section
Friday–Sunday, November 3–5, 2023;
University of Delaware, Newark, Delaware
Session C02: Two-Dimensional Magnetic Materials and Rare-Earth Free Magnets
9:00 AM–10:36 AM,
Saturday, November 4, 2023
University of Delaware
Room: Gore 104
Chair: Anish Rai, University of Delaware
Abstract: C02.00002 : Magnetic proximity coupling to defects in two-dimensional semiconductors*
9:36 AM–9:48 AM
Abstract
Presenter:
Muhammad Hassan Shaikh
(University of Delaware)
Authors:
Muhammad Hassan Shaikh
(University of Delaware)
Matt Whalen
(University of Delaware)
John Q Xiao
(University of Delaware)
Chitraleema Chakraborty
(University of Delaware)
Collaboration:
Aqiq Ishraq, Collin Maurtua, Shaidul Asif
Magnetically active defects have been extensively employed in quantum sensing applications, with nitrogen-vacancy centers in diamond and silicon-vacancy in silicon carbide being the most commonly used examples. However, their applicability to two-dimensional (2D) magnetic materials is limited due to the challenges associated with accessibility and interaction with surfaces. Conversely, defects in 2D materials, particularly transition metal dichalcogenides (TMDCs), have garnered significant attention. Optically active defects in TMDCs are highly sensitive to magnetic fields, providing an opportunity for direct probing of the layer-dependent magnetic properties at the nanoscale. Layer-dependent 2D magnets, such as Chromium thiophosphate (CrPS4), which display ferromagnetic (FM) and antiferromagnetic (AFM) properties depending on the layer count, have emerged as promising candidates for next-generation advanced spintronics devices. Previous studies have classified the bulk form of these materials as AFM using the Magnetic Optical Kerr Rotation technique, the magnetic behavior of the surface layer of bulk CrPS4 remains unexplored. To investigate the FM and AFM responses of the surface layers of bulk in these materials, we utilize magnetic proximity coupling with optically active defects in TMDCs. These defect-based quantum emitters offer higher spectral resolution compared to 2D excitonic transitions, which suffer from broad line widths, thereby enabling increased magnetic field sensitivity. In this study, we examine the magneto-photoluminescence of a heterostructure composed of CrPS4 and tungsten diselenide (WSe2), utilizing defect-based quantum emitters as optically active probes at low temperatures. The surface layer of bulk CrPS4 is found to exhibit a detectable net magnetic moment via the Degree of Circular Polarization of photoluminescence from the defect-based quantum emitters. We detect spin flip in bulk CrPS4 and quantify spin-polarized charge transfer between CrPS4 and WSe2 heterostructure. These findings provide valuable insights into the potential applications of next-generation AFM-based spintronics and advanced memory-based devices.
*NSF MRSEC