Voltage-Controlled Magnetism for Energy-Efficient Spintronics

Conventional spintronics-based memory devices use electrical currents to control electron spin direction and dynamics. While effective, this method has high energy costs and limited device endurance [1]. To address the demand for faster, smaller, and ultra-low-power electronic devices, research into voltage control of magnetism has recently intensified, promising ultra-low-power non-volatile memory solutions for next-generation computing systems [2]. We present our advancements in voltage-controlled magnetism through various approaches, including voltage-controlled magnetic anisotropy, voltage-controlled exchange coupling, and multiferroic-based magnetoelectric coupling for spintronics applications. Our studies have led to several significant discoveries. One key finding is the large tunability of perpendicular magnetic anisotropy (PMA) achieved by inserting ultrahin Ir, Mg-Al, and Pt layer at the MgO/Ferromagnet interface [3]. We also demonstrated the modulation of interlayer exchange coupling using an Ir spacer layer and non-ionic liquid gating like MgO [4]. This novel approach improves magnetic interaction control, reducing power consumption. Additionally, we showed that the magneto-electric coupling effect in a bismuth ferrite-based multiferroic system can modulate magnetism [5-7]. This discovery opens new possibilities for using multiferroic materials in spintronic applications, achieving low-power operation. These efforts offer multiple pathways to modulate resistance states in spintronic devices, paving the way for next-generation energy-efficient computing devices.<br/><br/><b>References</b><br/>[1] Bhagwati Prasad, Stuart Parkin, Themis Prodromakis, Chang-Beom Eom, Jordi Sort, JL MacManus-Driscoll, “<i>Material Challenges for Nonvolatile Memory</i>”, <b>APL Mater. 10, 090401 (2022).</b><br/>[2] Sasikanth Manipatruni, Dmitri E. Nikonov, Chia-Ching Lin, Tanay Gosavi, Huichu Li, Bhagwati Prasad, Yen Lin Huang, Ramamoorthy Ramesh, Ian A. Young_,“<i>Scalable Energy-Efficient Magnetoelectric Spin-Orbit Charge Logic</i>”, <b>Nature 565, 35 (2019)</b>.<br/>[3] Bhagwati Prasad*, Neil Smith, Lei Wan, Alan Kalitsov, Matt Carey, Jordan Katine, Tiffany Santos, " <i>Large Perpendicular Magnetic Anisotropy and Voltage Controlled Magnetic Anisotropy Effects at CoFe/MgO Interface</i>”, <b>Conference Paper: IEEE 32^nd Mangnetic Recordign Conference (TMRC) (2021).</b><br/>[4] Akash Surampalli, Anup Kumar Bera, Rajesh Chopdekar, Alan Kalitsov, Lei Wan, Jordan Katine, Derek Stewart, Tiffany Santos, and Bhagwati Prasad*, “<i>Voltage Controlled Interlayer Exchange Coupling and Magnetic Anisotropy Effects in Perpendicular Magnetic Heterostructures</i>”, <b>Accepted in Advanced Functional Materials (2024).</b><br/>[5]<i> Bhagwati Prasad*, et al. , “ Ultralow Voltage Manipulation of Ferromagnetism”, <b>Advanced Materials 32, 2001943 (2020).</b></i><br/>[6] Yen-Lin Huang, Dmitri Nikonov, Christopher Addiego, Rajesh V Chopdekar, Bhagwati Prasad, et al., “<i>Manipulating magnetoelectric energy landscape in multiferroics</i>”, <b>Nature Communication 11, 2836 (2020).</b><br/>[7] Diogo C Vaz, Chia-Ching Lin, John J Plombon, Won Young Choi, Inge Groen, Isabel C Arango, Andrey Chuvilin, Luis E Hueso, Dmitri E Nikonov, Hai Li, Punyashloka Debashis, Scott B Clendenning, Tanay A Gosavi, Yen-Lin Huang, Bhagwati Prasad, Ramamoorthy Ramesh, Aymeric Vecchiola, Manuel Bibes, Karim Bouzehouane, Stephane Fusil, Vincent Garcia, Ian A Young, Fèlix Casanova, “<i>Voltage-based magnetization switching and reading in magnetoelectric spin-orbit nanodevices</i>”, <b>Nature Communications </b><b>15, 1902, (2024).</b>