More Like this

1. Extraordinary tunnel electroresistance in layer-by-layer engineered van der Waals ferroelectric tunnel junctions

   https://doi.org/10.1016/j.matt.2022.10.014  

   Wang, Qinqin; Xie, Ti; Blumenschein, Nicholas A.; Song, Zhihao; Kotsakidis, Jimmy C.; Hanbicki, Aubrey T.; Susner, Michael A.; Conner, Benjamin S.; Tan, Qishuo; Lee, Seng Huat; et al (December 2022, Matter)
2. Tunnel magnetoresistance detection of skyrmions

   https://doi.org/10.1016/j.jmmm.2021.168552  

   Chen, Hao; Bouckaert, William; Majetich, Sara A. (January 2022, Journal of Magnetism and Magnetic Materials)
3. Antiferromagnetic tunnel junctions for spintronics

   https://doi.org/10.1038/s44306-024-00014-7  

   Shao, Ding-Fu; Tsymbal, Evgeny Y (December 2024, npj Spintronics)

   Abstract Antiferromagnetic (AFM) spintronics has emerged as a subfield of spintronics, where an AFM Néel vector is used as a state variable. Efficient electric control and detection of the Néel vector are critical for spintronic applications. This review article features fundamental properties of AFM tunnel junctions (AFMTJs) as spintronic devices where such electric control and detection can be realized. We emphasize critical requirements for observing a large tunneling magnetoresistance (TMR) effect in AFMTJs with collinear and noncollinear AFM electrodes, such as a momentum-dependent spin polarization and Néel spin currents. We further discuss spin torques in AFMTJs that are capable of Néel vector switching. Overall, AFMTJs have potential to become a new standard for spintronics providing larger magnetoresistive effects, few orders of magnitude faster switching speed, and much higher packing density than conventional magnetic tunnel junctions (MTJs). 

   more » « less
4. Three-dimensional Topological Insulator Tunnel Diodes

   Fluckey, Stephen P.; Tiwari, Sabyasachi; Hinkle, Christopher L.; Vandenberghe, William G. (January 2022, Physical review)

   Topological insulators open many avenues for designing future electronic devices. Using the Bardeen transfer Hamiltonian method, we calculate the current density of electron tunneling between two slabs of Bi2Se3. 3D TI tunnel diode current-voltage characteristics are calculated for different doping concentrations, tunnel barrier height and thickness, and 3D TI bandgap. The difference in the Fermi levels of the slabs determines the peak and trough voltages. The tunnel barrier width and height affect the magnitude of the current without affecting the shape of the current-voltage characteristics. The bandgap of the 3D TI determines the magnitude of the tunnel current, albeit at a lesser rate than the tunnel barrier potential, thus the device characteristics are robust under changing TI material. The high peak-to-trough ratio of 3D TI tunnel diodes, the controllabilty of the trough current location, and the simple construction provide advantages over other NDR devices. 

   more » « less
5. Vertical Organic Tunnel Field-Effect Transistors

   Liu, Shiyi; Tietze, Max; Al-Shadeedi, Akram; Kaphle, Vikash; Keum, Changmin; Lussem, Bjorn (July 2019, ACS applied electronic materials)

   Doping organic semiconductors has become a key technology to increase the performance of organic light-emitting diodes, solar cells, or field-effect transistors (OFETs). However, doping can be used not only to optimize these devices but also to enable new design principles as well. Here, a novel type of OFET is reported—the vertical organic tunnel field-effect transistor. Based on heterogeneously doped drain and source contacts, charge carriers are injected from an n-doped source electrode into the channel by Zener tunneling and are transported toward a p-doped drain electrode. The working mechanism of these transistors is discussed with the help of a tunnel model that takes energetic broadening of transport states in organic semiconductors and roughness of organic layers into account. The proposed device principle opens new ways to optimize OFETs. It is shown that the Zener junction included between the source and drain of the vertical organic tunnel field-effect transistors suppresses short channel effects and improves the saturation of vertical OFETs. 

   more » « less