Bulletin of the American Physical Society
APS March Meeting 2021
Volume 66, Number 1
Monday–Friday, March 15–19, 2021; Virtual; Time Zone: Central Daylight Time, USA
Session P49: New Opportunities for Spin and Charge Control with α-RuCl3Invited Live
|
Hide Abstracts |
Sponsoring Units: DCMP Chair: Erik Henriksen, Washington University, St. Louis |
Wednesday, March 17, 2021 3:00PM - 3:36PM Live |
P49.00001: α-RuCl3 on graphene: subtle interplay of spin, charge and strain effects Invited Speaker: Roser Valenti In the pursuit of developing routes to enhance magnetic Kitaev interactions in α-RuCl3, as well as probing doping effects, I will discuss in this talk possible new phases emerging from heterostructures of α-RuCl3 on graphene, based on ab initio combined with many-body simulations [1,2] and comparison to experimental observations such as recent electrical conductance and anomalous quantum oscillations measurements. |
Wednesday, March 17, 2021 3:36PM - 4:12PM Live |
P49.00002: Modulation doping in RuCl3 heterostructures Invited Speaker: Yiping Wang Two-dimensional (2d) nano-electronics, plasmonics, and emergent phases require clean and local charge control, calling for layered, crystalline acceptors or donors. Here, we demonstrate that the large work function narrow-band Mott insulator RuCl3 enables modulation doping of exfoliated single and bilayer graphene, chemical vapor deposition (CVD) grown graphene and WSe2, and molecular beam epitaxy (MBE) grown EuS. OurRaman measurements show high hole densities 3*1013cm-2 in mlg RuCl3 heterostructures and 6*1013cm-2 in bilayer graphene (blg) RuCl3 heterostructures. In addition, our study suggest photovoltage devices, charge transfer control via twist angle, and charge transfer through hexagonal boron nitride (hBN). |
Wednesday, March 17, 2021 4:12PM - 4:48PM Live |
P49.00003: Mismatched INterface Theory (MINT) and its integration into open-access database Invited Speaker: Eun-Ah Kim Recent developments in 2D incommensurate atomic heterostructures reveal a vast phase space of complex systems, rich in exotic phenomena and opportunities for control. Among these systems are hetero-bilayers, which can offer new opportunities to create designed interfacial systems. Nevertheless, the non-crystalline nature of such systems challenges ab initio predictions for the interfaces. |
Wednesday, March 17, 2021 4:48PM - 5:24PM Live |
P49.00004: Charge-Transfer Plasmon Polaritons at Graphene/α-RuCl3 Interfaces Invited Speaker: Daniel Joseph Rizzo The fundamental opto-electronic properties of two-dimensional (2D) materials can be tailored based on their nanoscale charge environment. While electrostatic doping offers a means of wholesale tuning of 2D charge densities, the minimum size of charge features is limited by fields fringing through relatively thick gate insulators. Conversely, charge transfer at the interface of two atomically-thin layers with different work functions should not be subject to such limitations. Specifically, the large work function of α-RuCl3 (6.1 eV) makes it an ideal 2D electron acceptor. In our study, we exploit this behavior to generate charge-transfer plasmon polaritons (CPPs) in graphene/α-RuCl3 heterostructures. Using infrared near-field optical microscopy we measure the CPP dispersion, yielding a quantitative measure of the graphene Fermi energy (~0.6 eV) and thus the charge exchanged between α-RuCl3 and graphene (~2.7x1013 cm–2). Concurrently, we observe dispersive edge modes and internal “circular” CPPs which reveal sharp (< 50 nm) changes in the graphene optical conductivity that correspond to nanoscale modulations in the graphene doping level. Further analysis of the CPP losses implies the presence of emergent optical conductivity in the doped interfacial layer of α-RuCl3 and suggests that it no longer possesses a Mott insulating ground state. Our results demonstrate that using high work function materials such as α-RuCl3 in Van der Waals heterostructures presents new opportunities for controlling the local charge carrier density of graphene and other 2D materials on nanometer length scales in excess of what can be achieved with an external gate. |
Wednesday, March 17, 2021 5:24PM - 6:00PM Live |
P49.00005: Proximity induced charge transfer and anomalous temperature dependency in G/α-RuCl3 Invited Speaker: Soudabeh Mashhadi Proximity effects in van der Waals heterostructures have proven to be a powerful means to induce a wide range of interfacial phenomena. Among van der Waals materials, α-RuCl3 has attracted attention as a candidate platform to host the sought-after Kitaev quantum spin liquid phase owing to its frustrated spin interactions on the honeycomb lattice. However, due to strong Mott insulating behavior, probing electronic and magnetic properties of α-RuCl3 using transport measurements is not possible. In this presentation, I will discuss graphene/α-RuCl3 heterostructures as a novel platform for mutually altering the electronic properties of both graphene and α-RuCl3. Quantum oscillations and Hall measurements provide clear evidence for a band realignment that is accompanied by a large transfer of electrons originally occupying the graphene’s spin degenerate Dirac cones into α-RuCl3 band with in-plane spin polarization. Furthermore, the temperature dependent measurements of the quantum oscillations reveal a non-Lifshitz-Kosevich behavior. The origin of this anomalous temperature behavior is studied by varying the thickness of the α-RuCl3 layer, point to an interplay with the underlying delicate magnetic texture of the material in the thin-limit. |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700