Publications by authors named "J Appenzeller"
Fundamental Understanding of Interface Chemistry and Electrical Contact Properties of Bi and MoS.
ACS Appl Mater Interfaces
October 2024
The interface properties and thermal stability of bismuth (Bi) contacts on molybdenum disulfide (MoS) shed light on their behavior under various deposition conditions and temperatures. The examination involves extensive techniques including X-ray photoelectron spectroscopy, scanning tunneling microscopy (STM), and scanning tunneling spectroscopy (STS). Bi contacts formed a van der Waals interface on MoS regardless of deposition conditions, such as ultrahigh vacuum (UHV, 3 × 10 mbar) and high vacuum (HV, 4 × 10 mbar), while the oxidation on MoS has been observed.
View Article and Find Full Text PDFReducing the dimensions of materials from three to two, or quasi-two, provides a fertile platform for exploring emergent quantum phenomena and developing next-generation electronic devices. However, growing high-quality, ultrathin, quasi2D materials in a templated fashion on an arbitrary substrate is challenging. Here, the study demonstrates a simple and reproducible on-chip approach for synthesizing non-layered, nanometer-thick, quasi-2D semimetals.
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- Ternary content-addressable memory (TCAM) is a next-gen memory type that's ideal for AI applications because it can handle many data operations simultaneously.
- Researchers have developed a single transistor TCAM using a unique floating-gate design with 2D materials, which may outperform traditional silicon in terms of scalability.
- This new TCAM cell not only boasts a high resistance ratio and symmetrical states but also supports efficient in-memory computations, like Hamming distance calculations, with potential implementations of large arrays.
Article Synopsis
- Contact engineering of monolayer semiconducting transition metal dichalcogenides (TMDs) presents challenges for their use in transistors due to the strong Fermi-level pinning, which creates high Schottky barriers that reduce device performance.
- This study involved extensive electrical measurements and surface analysis of over 120 field-effect transistors (FETs), revealing that lower contact resistance is achieved with nickel contacts deposited under ultrahigh-vacuum (UHV) conditions compared to high-vacuum (HV) conditions.
- The findings highlight significant differences in interface chemistry revealed by X-ray photoelectron spectroscopy (XPS), which correlate with the observed performance, and also investigate the reliability of nickel and bismuth contact metals under
Probabilistic computing is a computing scheme that offers a more efficient approach than conventional complementary metal-oxide-semiconductor (CMOS)-based logic in a variety of applications ranging from optimization to Bayesian inference, and invertible Boolean logic. The probabilistic bit (or p-bit, the base unit of probabilistic computing) is a naturally fluctuating entity that requires tunable stochasticity; by coupling low-barrier stochastic magnetic tunnel junctions (MTJs) with a transistor circuit, a compact implementation is achieved. In this work, by combining stochastic MTJs with 2D-MoS field-effect transistors (FETs), we demonstrate an on-chip realization of a p-bit building block displaying voltage-controllable stochasticity.
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