Intercorrelated ferroelectrics in 2D van der Waals materials

AbstractWith the outstanding mechanical properties, van der Waals (vdW) materials have attracted extensive attention in the research of straintronics in the past decade. In this perspective, we first review the recent progresses of the straintronics with vdW materials based on three different lattice deformation modes, i.e., in-plane strain, out-of-plane strain, and heterostrain. Then we discuss the current technique challenges in this field, and finally provide our perspectives on future research directions for both fundamental physics and electronic applications.

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Chemical Pressure Boost Record‐High Superconductivity in van der Waals Materials FeSe 1− x S x

Advanced Functional Materials ◽

10.1002/adfm.202102917 ◽

2021 ◽

pp. 2102917

Author(s):

Ruijin Sun ◽

Shifeng Jin ◽

Jun Deng ◽

Munan Hao ◽

Xin Zhong ◽

...

Keyword(s):

Van Der Waals ◽

Chemical Pressure ◽

Van Der Waals Materials

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Carrier-capture-assisted optoelectronics based on van der Waals materials to imitate medicine-acting metaplasticity

npj 2D Materials and Applications ◽

10.1038/s41699-021-00241-0 ◽

2021 ◽

Vol 5 (1) ◽

Author(s):

Qianfan Nie ◽

Caifang Gao ◽

Feng-Shou Yang ◽

Ko-Chun Lee ◽

Che-Yi Lin ◽

...

Keyword(s):

Weight Change ◽

Synaptic Weight ◽

Van Der Waals ◽

Low Frequency ◽

Photonic Devices ◽

Frequency Noise ◽

Carrier Capture ◽

Electronic Engineering ◽

Neural Simulation ◽

Van Der Waals Materials

AbstractRecently, researchers have focused on optoelectronics based on two-dimensional van der Waals materials to realize multifunctional memory and neuron applications. Layered indium selenide (InSe) semiconductors satisfy various requirements as photosensitive channel materials, and enable the realization of intriguing optoelectronic applications. Herein, we demonstrate InSe photonic devices with different trends of output currents rooted in the carrier capture/release events under various gate voltages. Furthermore, we reported an increasing/flattening/decreasing synaptic weight change index (∆Wn) via a modulated gate electric field, which we use to imitate medicine-acting metaplasticity with effective/stable/ineffective features analogous to the synaptic weight change in the nervous system of the human brain. Finally, we take advantage of the low-frequency noise (LFN) measurements and the energy-band explanation to verify the rationality of carrier capture-assisted optoelectronics applied to neural simulation at the device level. Utilizing optoelectronics to simulate essential biomedical neurobehaviors, we experimentally demonstrate the feasibility and meaningfulness of combining electronic engineering with biomedical neurology.

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X-ray spectra in the magnetic van der Waals materials Fe3GeTe2, CrI3, and CrGeTe3 : A first-principles study

Physical Review B ◽

10.1103/physrevb.103.134407 ◽

2021 ◽

Vol 103 (13) ◽

Author(s):

Y. Lee ◽

V. N. Antonov ◽

B. N. Harmon ◽

Liqin Ke

Keyword(s):

First Principles ◽

Van Der Waals ◽

X Ray ◽

First Principles Study ◽

Van Der Waals Materials

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A van der Waals antiferromagnetic topological insulator with weak interlayer magnetic coupling

Nature Communications ◽

10.1038/s41467-019-13814-x ◽

2020 ◽

Vol 11 (1) ◽

Cited By ~ 36

Author(s):

Chaowei Hu ◽

Kyle N. Gordon ◽

Pengfei Liu ◽

Jinyu Liu ◽

Xiaoqing Zhou ◽

...

Keyword(s):

Van Der Waals ◽

Surface States ◽

Magnetic Coupling ◽

Anomalous Hall Effect ◽

Saturation Field ◽

Angle Resolved Photoemission Spectroscopy ◽

Ideal System ◽

Out Of Plane ◽

Weak Interlayer ◽

Quantum Phenomena

AbstractMagnetic topological insulators (TI) provide an important material platform to explore quantum phenomena such as quantized anomalous Hall effect and Majorana modes, etc. Their successful material realization is thus essential for our fundamental understanding and potential technical revolutions. By realizing a bulk van der Waals material MnBi4Te7 with alternating septuple [MnBi2Te4] and quintuple [Bi2Te3] layers, we show that it is ferromagnetic in plane but antiferromagnetic along the c axis with an out-of-plane saturation field of ~0.22 T at 2 K. Our angle-resolved photoemission spectroscopy measurements and first-principles calculations further demonstrate that MnBi4Te7 is a Z2 antiferromagnetic TI with two types of surface states associated with the [MnBi2Te4] or [Bi2Te3] termination, respectively. Additionally, its superlattice nature may make various heterostructures of [MnBi2Te4] and [Bi2Te3] layers possible by exfoliation. Therefore, the low saturation field and the superlattice nature of MnBi4Te7 make it an ideal system to investigate rich emergent phenomena.

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Consecutive Vibrational Redistribution and Predissociation Processes in s-Tetrazine–Argon Van Der Waals Complexes

Laser Chemistry ◽

10.1155/lc.2.125 ◽

1983 ◽

Vol 2 (3-4) ◽

pp. 125-135 ◽

Cited By ~ 19

Author(s):

J. J. F. Ramaekers ◽

L. B. Krijnen ◽

H. J. Lips ◽

J. Langelaar ◽

R. P. H. Rettschnick

Keyword(s):

Decay Time ◽

Van Der Waals ◽

Stagnation Pressure ◽

Van Der Waals Complexes ◽

Supersonic Expansion ◽

Vibrational Predissociation ◽

Out Of Plane ◽

Spectrally Resolved ◽

Plane Mode

s-Tetrazine argon complexes T−Arn (n = 1, 2) are formed in a supersonic expansion of argon seeded with s-tetrazine. The expansion was conducted through a nozzle of 50 or 100 μm with an argon stagnation pressure between 1 and 1.5 bar. From spectrally resolved measurements it is clear that vibrational redistribution processes as well as vibrational predissociation processes take place after SVL excitation within the complex.From rise and decay time experiments it can be concluded, that after excitation of the 6a1 complex level, the above mentioned processes are consecutive and not parallel. It appears that the out of plane mode 16a couples with the Van der Waals stretching mode. The predissociation rate of the 16a2 complex is observed to be 2.3 × 109 s−1.

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2D van der Waals materials for ultrafast pulsed fiber lasers: review and prospect

Nanotechnology ◽

10.1088/1361-6528/ac3611 ◽

2021 ◽

Author(s):

Yani Zhang ◽

Zhuo-ying Song ◽

Dun Qiao ◽

Xiaohui Li ◽

Zhe Guang ◽

...

Keyword(s):

Fiber Lasers ◽

Van Der Waals ◽

Fast Response ◽

High Threshold ◽

Absorption Characteristic ◽

Saturable Absorption ◽

Metal Chalcogenides ◽

Ultrafast Optical ◽

Van Der Waals Materials ◽

Pulsed Fiber Lasers

Abstract 2D van der Waals materials are crystals composed of atomic layers, which have atomic thickness scale layers and rich distinct properties, including ultrafast optical response, surface effects, light-mater interaction, small size effects, quantum effects and macro quantum tunnel effects. With the exploration of saturable absorption characteristic of 2D van der Waals materials, a series of potential applications of 2D van der Waals materials as high threshold, broadband and fast response saturable absorbers (SAs) in ultrafast photonics have been proposed and confirmed. Herein, the photoelectric characteristics, nonlinear characteristic measurement technique of 2D van der Waals materials and the preparation technology of SAs are systematically described. Furthermore, the ultrafast pulsed fiber lasers based on classical 2D van der Waals materials including graphene, Transition Metal Chalcogenides (TMCs), Topological Insulators (TIs) and Black Phosphorus (BP) have been fully summarized and analyzed. On this basis, opportunities and directions in this field, as well as the research results of ultrafast pulsed fiber lasers based on the latest 2D van der Waals materials (such as PbO, FePSe3, graphdiyne, bismuthene, Ag2S and MXene etc.), are reviewed and summarized.

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Tin diselenide van der Waals materials as new candidates for mid-infrared waveguide chips

Nanoscale ◽

10.1039/c9nr04264d ◽

2019 ◽

Vol 11 (30) ◽

pp. 14113-14117 ◽

Cited By ~ 2

Author(s):

Mengfei Xue ◽

Qi Zheng ◽

Runkun Chen ◽

Lihong Bao ◽

Shixuan Du ◽

...

Keyword(s):

Near Field ◽

Van Der Waals ◽

Building Blocks ◽

Two Dimensional ◽

Mid Infrared ◽

Near Field Imaging ◽

Van Der Waals Materials ◽

Field Imaging

Near-field imaging of mid-infrared waveguide in SnSe2 slabs promotes two-dimensional van der Waals materials as building blocks for integrated MIR chips.

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Temperature and interlayer coupling induced thermal transport across graphene/2D-SiC van der Waals heterostructure

Scientific Reports ◽

10.1038/s41598-021-04740-4 ◽

2022 ◽

Vol 12 (1) ◽

Author(s):

Md. Sherajul Islam ◽

Imon Mia ◽

A. S. M. Jannatul Islam ◽

Catherine Stampfl ◽

Jeongwon Park

Keyword(s):

High Temperatures ◽

Thermal Transport ◽

Van Der Waals ◽

Thermal Conductance ◽

Interlayer Coupling ◽

Phonon Modes ◽

Out Of Plane ◽

System Temperature ◽

Non Equilibrium Molecular Dynamics ◽

Increasing Temperature

AbstractGraphene based two-dimensional (2D) van der Waals (vdW) materials have attracted enormous attention because of their extraordinary physical properties. In this study, we explore the temperature and interlayer coupling induced thermal transport across the graphene/2D-SiC vdW interface using non-equilibrium molecular dynamics and transient pump probe methods. We find that the in-plane thermal conductivity κ deviates slightly from the 1/T law at high temperatures. A tunable κ is found with the variation of the interlayer coupling strength χ. The interlayer thermal resistance R across graphene/2D-SiC interface reaches 2.71 $$\times$$ × 10–7$${\text{Km}}^{2} /{\text{W}}$$ Km 2 / W at room temperature and χ = 1, and it reduces steadily with the elevation of system temperature and χ, demonstrating around 41% and 56% reduction with increasing temperature to 700 K and a χ of 25, respectively. We also elucidate the heat transport mechanism by estimating the in-plane and out-of-plane phonon modes. Higher phonon propagation possibility and Umklapp scattering across the interface at high temperatures and increased χ lead to the significant reduction of R. This work unveils the mechanism of heat transfer and interface thermal conductance engineering across the graphene/2D-SiC vdW heterostructure.

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