High performance ultrascaled monolayer/bilayer WSe2 FETs achieved by immaculate 2D/2D contacts DOI Creative Commons
Joerg Appenzeller, Zheng Sun, Aryan Afzalian

et al.

Research Square (Research Square), Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 20, 2024

Abstract Achieving low contact resistance in p-type transistors remains a critical challenge when using transition-metal dichalcogenides (TMDs) as channel materials. Deposition of high work function metals at elevated temperatures often causes defects or strain the metal/channel interface, which turn can result an increased resistance. Metallic two-dimensional (2D) materials offer promising solution this context due to their low-temperature formation and atomically flat surfaces. However, experimental progress has been slow part rather large bandgap monolayer WSe2. Here, we report novel approach, metallic layered Nb0.3W0.7Se2 for bilayer WSe2 with lengths down 100 nm. Combined ultra-scaled gate dielectrics effective oxide thickness (EOT) 1.3nm, resulting 2D/2D contacted FETs exhibit on-current densities up 375 µA/µm 1.1 mA/µm on channel, respectively. This method also enables fabrication devices achieving subthreshold swings small 88 mV/dec.

Language: Английский

Superconductivity in 5.0° twisted bilayer WSe2 DOI

Yinjie Guo,

Jordan Pack,

Joshua Swann

et al.

Nature, Journal Year: 2025, Volume and Issue: 637(8047), P. 839 - 845

Published: Jan. 22, 2025

Language: Английский

Citations

13
Unraveling the Role of Interfacial Interactions in Electrical Contacts of Atomically Thin Transition-Metal Dichalcogenides DOI

Meiying Gong,

Dabao Xie,

Yiqian Tian

et al.

ACS Nano, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 23, 2025

Van der Waals (vdW) contact has been widely regarded as one of the most potential strategies for exploiting low-resistance metal-semiconductor junctions (MSJs) based on atomically thin transition-metal dichalcogenides (TMDs), but this method is still not efficient due to weak metal-TMD interfacial interactions. Therefore, an understanding interactions between metals and TMDs essential achieving contacts with Fermi level pinning (FLP). Herein, we report how affect electrical by considering more than 90 MSJs consisting a semiconducting TMD channel different types metal electrodes, including bulk metals, MXenes, metallic TMDs. We reveal that vdW scheme cannot ensure formation contacts. The coupling leads delicate competition FLP carrier tunneling efficiency, which explains broad experimental observations in weakly coupled van usually show high resistance, while strongly suffer from strong FLP. Benefiting low Schottky barrier FLP, Ag promising electrode n-type MoS2 devices resistance 83 Ω μm at concentration 5.95 × 1013 cm-2, 1T'-phase Sc2NO2 are identified superior electrodes p-type WSe2 devices. This work offers general rule exploit high-performance clarifies key role TMD-based

Language: Английский

Citations

2
Non-Abelian Fractionalization in Topological Minibands DOI
Aidan P. Reddy, Nisarga Paul, Ahmed Abouelkomsan

et al.

Physical Review Letters, Journal Year: 2024, Volume and Issue: 133(16)

Published: Oct. 17, 2024

Motivated by the recent discovery of fractional quantum anomalous Hall states in moiré systems, we consider possibility realizing non-Abelian phases topological minibands. We study a family skyrmion Chern band models, which can be realized two-dimensional semiconductor-magnet heterostructures and also capture essence twisted transition metal dichalcogenide homobilayers. show using many-body exact diagonalization that, spite strong Berry curvature variations momentum space, Moore-Read state at half filling second miniband. These results demonstrate feasibility fractionalization systems without Landau levels shed light on desirable conditions for their realization. In particular, highlight prospect semiconductor bilayers.

Language: Английский

Citations

16
Ultrafast Hot Carrier Cooling Enabled van der Waals Photodetectors at Telecom Wavelengths DOI Creative Commons

Zhouxiaosong Zeng,

Yufan Wang, Patrick Michel

et al.

Nano Letters, Journal Year: 2025, Volume and Issue: 25(9), P. 3497 - 3504

Published: Feb. 24, 2025

Two-dimensional (2D) materials with high carrier mobility and picosecond intrinsic response times exhibit large potential for fast optoelectronics operating at telecom wavelengths. However, due to the inefficient utilization of hot carriers, 2D photodetectors C-band have rarely been realized. Here, we report a high-performance waveguide-free WS2/graphene photodetector 1560 nm enabled by injection long-lived charge separation. The efficiently injected electrons from graphene WS2 ultrafast cooling dynamics 3 ps time. Simultaneous hole trapping in ensures long circulation electrons, enabling responsivity 0.26 A/W. In continuation, present vertical WS2/graphene/WSe2 device built-in electric field same detection mechanism, which photocurrent on-off ratio 3500 an extrinsic time 1.71 ns are obtained. Our study highlights benefit combining semiconductors semimetals high-speed photodetection.

Language: Английский

Citations

1
Contact resistance and interfacial engineering: Advances in high-performance 2D-TMD based devices DOI
Xiongfang Liu, Kaijian Xing, Chi Sin Tang

et al.

Progress in Materials Science, Journal Year: 2024, Volume and Issue: unknown, P. 101390 - 101390

Published: Oct. 1, 2024

Language: Английский

Citations

5
Edge-Mediated Charge Deposition at 2D Contact DOI

Zipei Tan,

Xuanyu Huang,

Jinbo Bian

et al.

ACS Applied Materials & Interfaces, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 15, 2025

Electrical charge deposition modulates carrier mobility in electronic devices and governs interfacial processes such as frictional energy dissipation triboelectric power generation. Selective on 2D materials enables logic memory functions, but controlling transfer trapping remains a challenge. Here, we report an unconventional contact electrification mechanism activated at sliding structural superlubric interface between highly ordered pyrolytic graphite h-BN. Spatially controlled is achieved through mechanical manipulation the front reversible way, while face-to-face intact even under pressures exceeding strength of most materials. First-principles calculations reveal that edge facilitates electron transfer, with driven by chemical potential difference across graphite/h-BN stabilized surface adsorbates.

Language: Английский

Citations

0
Engineering interfacial charge transfer through modulation doping for 2D electronics DOI
Raagya Arora, Ariel Barr, Daniel T. Larson

et al.

Physical Review Materials, Journal Year: 2025, Volume and Issue: 9(2)

Published: Feb. 18, 2025

Language: Английский

Citations

0
Ultrafast and Highly Mobile Photocarriers in Monolayer WSe2 Doped by α-RuCl3 DOI
Ting Zheng,

Emma Low,

Neema Rafizadeh

et al.

Nano Letters, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 26, 2025

We report an experimental investigation of photocarrier dynamics in a heterostructure formed by WSe2 monolayer stacked on multilayer α-RuCl3 flake. The samples were fabricated using mechanical exfoliation and dry transfer techniques. Photoluminescence measurements showed that the excitonic photoluminescence is quenched more than 3 orders magnitude upon contact with α-RuCl3. Transient absorption revealed ultrashort lifetime 0.5 ps heterostructure. Spatially resolved transient microscopy employed to probe transport properties these photocarriers, resulting room-temperature diffusion coefficient 370 cm2 s–1, which higher exciton coefficients most previously studied 2D semiconductors. These results suggest α-RuCl3-doped could be utilized high-speed optoelectronic devices.

Language: Английский

Citations

0
Disorder- and Interaction-Driven Quantum Criticality in WSe2 DOI
Nasir Ali, Fida Ali,

Hyungyu Choi

et al.

ACS Nano, Journal Year: 2025, Volume and Issue: unknown

Published: March 20, 2025

Quantum fluctuations resulting from strong Coulomb interactions or disorders lead to quantum phase transitions (QPTs) in 2D materials. However, understanding of disorder- and interaction-driven QPTs remains a fundamental challenge materials owing the presence disorder interactions. Here, we study systematic interplay by controlling thickness WSe2 elucidate metal-insulator QPTs. An observation (MITs) with conductivity ∼e2/h thin-WSe2 agrees Mott-Ioffe-Regel limit, excluding bad-metal behavior; conversely, MITs

Language: Английский

Citations

0
Nonsaturated large magnetoresistance and transport dynamics in a n-doped cryogenic WSe2 field-effect device DOI
Wei‐Chen Lin, Ching-Chen Yeh,

Jia-Zhu Zou

et al.

Physical review. B./Physical review. B, Journal Year: 2025, Volume and Issue: 111(12)

Published: March 24, 2025

Interest in the two-dimensional (2D) semiconducting transition metal dichalcogenides (TMDs) continues to intensify, driven by their suitable band gaps supplant silicon as next-generation semiconductor materials. Among various TMDs, tungsten diselenide ($\mathrm{WS}{\mathrm{e}}_{2}$) is renowned for its superior electrical properties carrier density and mobility under ambient conditions. Despite notable attributes, behavior of monolayer $\mathrm{WS}{\mathrm{e}}_{2}$ electron-doped regime cryogenic conditions remains largely uncharted, particularly concerning magnetotransport properties. In this study, we reveal transport mechanisms from high temperatures down regime. As evident Efros--Shklovskii variable-range hopping (E-S VRH) regime, strong Coulomb interactions arise between electrons. Above 8 K, an uncommon nonsaturated quadratic large magnetoresistance (MR) can be explained wave-function shrinkage model, which consistent with E-S VRH mechanism. Notably, MR shows a magnitude up 1740% at 13 T. These findings underscore potential applications field-effect devices, magnetic sensors, memory devices mark significant advance research.

Language: Английский

Citations

0