Related Experiment Video
Updated: Aug 16, 2026

Advanced Experimental Methods for Low-temperature Magnetotransport Measurement of Novel Materials
Published on: January 21, 2016
Breaking voltage-controlled magnetic anisotropy-magnetoresistance trade-off for ultralow-energy switching in magnetic
Yu Zhang1, Meng Xu1, Bowei Zhou1
1Department of Physics, University of Arizona, Tucson, AZ 85721, USA.
Abstract:
Electric-field control of spin states offers a promising route to ultralow-power, ultrafast magnetization switching in spintronic devices such as magnetic tunnel junctions (MTJs). However, enhancing voltage-controlled magnetic anisotropy (VCMA) through interfacial engineering often disrupts coherent tunneling and suppresses tunnel magnetoresistance (TMR), limiting practical device performance. Here, we experimentally demonstrate highly energy-efficient, voltage-driven magnetization switching in MTJs enabled by a remote iridium (Ir) doping strategy that tailors the Ir concentration near the MgO/CoFeB interface in the free layer. By inserting an ultrathin Ir layer away from the tunnel barrier and leveraging controlled diffusion during annealing, we achieve sub-nanosecond switching with an energy of only 3.5 femtojoules per bit in nanoscale MTJs while maintaining a TMR ratio up to 160% after 400°C postannealing. These results resolve a long-standing VCMA-TMR trade-off and establish a scalable pathway toward ultralow-power nonvolatile spintronic devices under aggressive energy and scaling constraints.
Related Concept Videos
Characteristics of MOSFET
Various vital parameters influence their functionality, which is crucial for theory and electronics applications. First, channel dimensions, precisely length, and width, are pivotal. The size of these channels affects the transistor's ability to carry current and switching speeds; shorter channels typically enable quicker...
Biasing of Metal-Semiconductor Junctions
In Schottky junctions, where the semiconductor is n-type, applying a positive voltage to the metal relative to the semiconductor reduces its Fermi...
MOSFET: Enhancement Mode
In their basic form, enhancement-mode MOSFETs are typically non-conductive when the gate-source voltage (Vgs) is zero. This default 'off' state means no current...
Ferromagnetism
Biasing of FET
In an N-channel JFET, the structure consists of N-type material forming the channel on a P-type substrate, with the gate...
Paramagnetism

