Article
Physics, Multidisciplinary
Ming Li, Zi-Liang Cai, Zhi-Bo Feng, Zheng-Yin Zhao
Summary: This study investigates the valley-resolved transport properties of zigzag graphene nanoribbon (ZGNR) junctions using the transfer matrix and Green's function methods. It is found that by adjusting the width of ZGNRs, the valley polarization efficiency and transmission coefficients can be controlled, which has potential applications in manipulating carrier transport properties at ZGNR junctions.
COMMUNICATIONS IN THEORETICAL PHYSICS
(2021)
Article
Physics, Condensed Matter
A. D. Lobanov, A. D. Lobanova, A. M. Pupasov-Maksimov
Summary: This paper investigates the Braess paradox in quantum transport, using the scattering matrix formalism to consider a two-parameter family of mesoscopic conductors with the topology of the classical Braess transport network. The study finds that the Braess paradox and normal transport regimes can coexist under the same congestion.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2022)
Article
Materials Science, Multidisciplinary
D. E. Tsurikov
Summary: Electron transport in branched semiconductor nanostructures can be calculated using a quantum network model. This model consists of three parts: the S-matrix of the network junction, the S-matrix of the network based on its junctions' S-matrices, and the electric currents through the network based on its S-matrix. The S-matrix of the network junction is calculated using scattering boundary conditions or alternative methods. The S-matrix of the network is calculated using a network combining formula. The electrical currents through the network are calculated using the Landauer-Buttiker formalism and extended scattering matrices. The proposed calculation scheme is demonstrated by modeling a nanostructure based on a two-dimensional electron gas. The electrical properties of the network are calculated at different temperatures.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2022)
Article
Multidisciplinary Sciences
Sangeeta Sharma, Peter Elliott, Samuel Shallcross
Summary: This study demonstrates that a hencomb pulse, which combines circularly polarized optical frequency pulse and linearly polarized THz pulse, can generate precisely tailored spin currents and valley currents in 2D materials. The control over these currents can be achieved by tuning the frequency and polarization vector of the light components. This result opens up a pathway for light control over spin/valley current states at ultrafast times.
Article
Physics, Condensed Matter
Vivek Prajapati, Nivedita Deo
Summary: This paper investigates the transport properties of mass-less and spin-less Dirac fermions in a substrate-induced graphene super-lattice. The study shows that by adjusting the structural parameters, the Dirac fermions can reflect and transmit between different valleys, leading to a unique behavior in the conductance.
PHYSICA B-CONDENSED MATTER
(2023)
Article
Nanoscience & Nanotechnology
Yinong Zhang, Chengxin Xiao, Dmitry Ovchinnikov, Jiayi Zhu, Xi Wang, Takashi Taniguchi, Kenji Watanabe, Jiaqiang Yan, Wang Yao, Xiaodong Xu
Summary: Monolayer semiconducting transition metal dichalcogenides possess broken inversion symmetry and strong spin-orbit coupling, resulting in a unique spin-valley locking effect. In stacked multilayers, this effect leads to the formation of a spin-valley locked superlattice structure. Dipolar excitons, which have the electron and hole constituents separated in an every-other-layer configuration, become optically bright through hybridization with intralayer excitons. The reflectance spectra further reveal the presence of excited state orbitals and fine spectroscopy structures, indicating a sizable binding energy.
NATURE NANOTECHNOLOGY
(2023)
Article
Nanoscience & Nanotechnology
Debaprem Bhattacharya, Debnarayan Jana
Summary: The new two-dimensional carbon allotrope TPDH-graphene has lower cohesive energy, good temperature stability, strong metallic electronic structure, superior mechanical properties compared to graphene, and characteristic peaks in electron energy loss spectra and optical reflectance peaks in the visible range. Some nanoribbons exhibit diverse behaviors and can be used in nanodevices with strong current regulation property and robust negative differential resistance effect.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2021)
Article
Chemistry, Physical
Wenzhe Zhou, Liang Wu, Aolin Li, Bei Zhang, Fangping Ouyang
Summary: The study demonstrates the spin-orbit coupling and valley-related properties of the monolayer WSi2N4 family, showing that changing the stacking can result in a Rashba spin-orbit field for controlling the spin direction of electrons. The characteristics of a Rashba semiconductor can be utilized for spin/valley Hall effects and manipulation of multiple degrees of freedom of electrons in monolayer materials.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Physics, Multidisciplinary
Yun-Lei Sun, Guo-Hong Chen, Si-Chao Du, Zhong-Bao Chen, Yan-Wei Zhou, En-Jia Ye
Summary: The spin-valley-related electronic properties of quasi-one-dimensional kagome lattices with intrinsic spin-orbit coupling are studied. It is found that spin-valley polarized edge states exist in the nanoribbons with different geometric boundaries, which has potential applications in devices.
FRONTIERS IN PHYSICS
(2022)
Article
Physics, Applied
Huating Liu, Zongyu Huang, Chaobo Luo, Gencai Guo, Xiangyang Peng, Xiang Qi, Jianxin Zhong
Summary: A novel heterobilayer Janus structure is designed by replacing chalcogenide atomic layers in bilayer MoS2, which exhibits direct band-gap semiconductor and typical type-II band alignment. Transition metal (TM) atoms (V/Cr/Mn) can be stably adsorbed on the heterobilayer Janus structure and introduce magnetic moments. The TM-SMoS/SeMoS system shows stable intrinsic anti-ferromagnetic or ferromagnetic interactions under different indirect exchange interactions, with high magnetic transition temperature.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2023)
Article
Multidisciplinary Sciences
Cedric Robert, Sangjun Park, Fabian Cadiz, Laurent Lombez, Lei Ren, Hans Tornatzky, Alistair Rowe, Daniel Paget, Fausto Sirotti, Min Yang, Dinh Van Tuan, Takashi Taniguchi, Bernhard Urbaszek, Kenji Watanabe, Thierry Amand, Hanan Dery, Xavier Marie
Summary: The study demonstrates efficient spin/valley optical pumping of resident electrons in n-doped WSe2 and WS2 monolayers, achieving large dynamic polarization of resident electrons using circular light with continuous wave laser and appropriate doping and excitation densities.
NATURE COMMUNICATIONS
(2021)
Article
Multidisciplinary Sciences
Zhen Bi, Liang Fu
Summary: Artificial moire superlattices in 2d van der Waals heterostructures provide a new avenue for realizing and controlling correlated electronic phenomena. A correlated insulator has recently been observed in twisted bilayer WSe2, believed to be an excitonic density wave due to intervalley electron-hole pairing. The insulating gap shows remarkable sensitivity to vertical electric fields, while being weakly affected by perpendicular magnetic fields, with potential detection through optical spin injection.
NATURE COMMUNICATIONS
(2021)
Article
Physics, Applied
Wan-Ying Li, Qing-Ping Wu, Zheng-Fang Liu, Fei-Fei Liu, Xian-Bo Xiao
Summary: We investigated the Andreev reflection of graphene-based normal/superconductor single and double junctions under the modulation of non-resonant circularly polarized light, staggered potential, and exchange field. The circularly polarized light can adjust the bandgap of retro Andreev reflection and specular Andreev reflection in single junctions, while the exchange field can change the position of the transition point between retro Andreev reflection and specular Andreev reflection. In double junctions, the valley-spin switching effect between pure elastic co-tunneling and pure crossed Andreev reflection can be realized by modulating the light field from left circularly polarized light to right circularly polarized light. By changing the exchange field, the conversion of non-local transport between pure elastic co-tunneling and pure crossed Andreev reflection can be achieved. The staggered potential and exchange field can control the energy location and range of crossed Andreev reflection and elastic co-tunneling.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
H. Khani
Summary: All-electrostatic generation and control of spin and valley polarizations in nanoscale devices is highly promising. This study demonstrates that the chiral spin-resolved topological edge states in two-dimensional hexagonal materials can overcome the limitation of broken time reversal symmetry. The bulk-to-edge transport in these materials allows for all-electrostatic generation and control of fully polarized spin-valley data, with perfect transmission that is insensitive to applied electric fields, making it a convenient approach for implementing spin and valley-based devices.
MATERIALS TODAY PHYSICS
(2022)
Article
Optics
Bei Yan, Yuchen Peng, Aoqian Shi, Jianlan Xie, Peng Peng, Jianjun Liu
Summary: This research explores the topological edge states and topological corner states formed by domain walls between different symmetric structures and verifies the realization of these states. The results have important implications for connecting waveguides with different symmetries to construct optical communication devices.
Article
Physics, Multidisciplinary
Ming Li, Zi-Liang Cai, Zhi-Bo Feng, Zheng-Yin Zhao
Summary: This study investigates the valley-resolved transport properties of zigzag graphene nanoribbon (ZGNR) junctions using the transfer matrix and Green's function methods. It is found that by adjusting the width of ZGNRs, the valley polarization efficiency and transmission coefficients can be controlled, which has potential applications in manipulating carrier transport properties at ZGNR junctions.
COMMUNICATIONS IN THEORETICAL PHYSICS
(2021)
Article
Physics, Condensed Matter
Ming Li, Zhi-Bo Feng, Zheng-Yin Zhao
Summary: Using the Green's function method, the modulation of conductance in zigzag graphene nanoribbon (ZGNR) junctions by gate voltages is studied. The conductance profiles are the same for different cases, except for displacement along the E-F axis, as long as the difference between the gate voltages applied to the left and right ZGNRs (ΔV) remains unchanged. The transmission of electrons from the upper/lower edge state of the left ZGNR to the lower/upper edge state of the right ZGNR is forbidden, resulting in an increase and then decrease in the width of the conductance gap as |ΔV| increases.
ADVANCES IN CONDENSED MATTER PHYSICS
(2023)
Article
Nanoscience & Nanotechnology
Spyridon G. Kosionis, Emmanuel Paspalakis
Summary: In this study, we theoretically investigate the pump-probe response and the four-wave mixing spectrum in a hybrid system composed of a semiconductor quantum dot and a spherical metal nanoparticle. Using a density matrix methodology, we calculate the absorption/gain, dispersion, and four-wave mixing spectra, and analyze their spectral characteristics. We also apply the metastate theory and the dressed-state picture to predict the positions of the spectral resonances.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2024)
Article
Nanoscience & Nanotechnology
L. S. Lima
Summary: This study investigates quantum correlation and entanglement in the non-Hermitian Hubbard model. By analyzing quantum entanglement measures such as entanglement negativity and entropy, the effect of non-Hermitian imaginary hopping on the system is explored. It is found that in the large... limit, the non-Hermiticity reverses the behavior of the ground state energy and low-lying excitations.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2024)
Article
Nanoscience & Nanotechnology
Nam-Chol Ri, Chung-Sim Kim, Sang-Ryol Ri, Su-Il Ri
Summary: By decreasing the lattice thermal conductivity of GNR through chemical derivation and strain, enhancing the thermoelectric properties of the electron part can be an important method to approach PGEC. This paper proposes synthesized hybrid systems formed by chemical derivation in the middle parts of b-AGNRs, and investigates the band structures and thermoelectric properties of the electron part under different strains. The results show that the band gaps of the systems significantly increase under different strains.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2024)
Article
Nanoscience & Nanotechnology
Le T. T. Phuong, Tran Cong Phong
Summary: This study investigates the effects of gas molecules adsorbed on /312-borophene on its electronic heat capacity and thermal Schottky anomaly. The results show that the adsorbed gas molecules have different impacts on the electronic heat capacity, leading to the generation of various new energy levels.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2024)
Article
Nanoscience & Nanotechnology
Tianyan Jiang, Jie Fang, Wentao Zhang, Maoqiang Bi, Xi Chen, Junsheng Chen
Summary: This paper investigates the adsorption and sensing properties of transition metal-doped WSSe gas-sensitive devices towards H2, CO, and CO2 gases related to thermal runaway in Li-ion batteries using density functional theory. The results show that Ti, Mn, and Mo dopants preferentially bind to the S-surface of the WSSe monolayer, and all three monolayers exhibit significantly improved sensing characteristics, with chemisorption towards CO. Band structure analysis suggests that the Ti-WSSe monolayer has the potential to be used as a resistive CO detection sensor. Recovery time calculations indicate the reuse capabilities of the gas-sensitive devices. Mn-WSSe monolayer shows potential for H2 detection, while Mo-WSSe monolayer is more suitable for CO2 detection. This work lays the foundation for potential gas-sensitive applications of WSSe monolayer in thermal runaway scenarios, advancing research in gas sensing domains.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2024)
Article
Nanoscience & Nanotechnology
Olga A. Alekseeva, Aleksandr A. Naberezhnov, Ekaterina Yu. Koroleva, Aleksandr Fokin
Summary: This study investigates the temperature dependence of crystal structure and dielectric response in a nanocomposite material containing porous glasses and embedded sodium nitrate. The results reveal a crossover point in the temperature dependence of the order parameter of the structural transition in sodium nitrate nanoparticles, as well as a decrease in activation energy of sodium ions hopping conductivity during heating.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2024)
Article
Nanoscience & Nanotechnology
Lijun Cheng, Fang Cheng
Summary: This paper investigates the effects of electric and magnetic fields on the Goos-Hanchen (GH) shift in a semi-Dirac system. The results show that the magnitude and direction of the GH shift depend on various factors such as incidence angle, electric barrier height and width, and magnetic field. It is observed that there is a saltus step in GH shifts at the critical magnetic field, which decreases with increased potential barrier thickness. Additionally, the GH shift can be significantly enhanced by applying an electric field in the III region. These findings are important for the development of semi-Dirac based electronic devices.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2024)
Article
Nanoscience & Nanotechnology
Alexander K. Fedotov, Uladzislaw E. Gumiennik, Julia A. Fedotova, Janusz Przewoznik, Czeslaw Kapusta
Summary: The study conducted an improved analysis of carrier transport in single-layer graphene and hybrid structures, showing the coexistence of negative and positive contributions in magnetoresistive effect. Various models were used to analyze the dependences on temperature and magnetic field, providing insights into the behavior of electrical resistance in the structures.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2024)
Article
Nanoscience & Nanotechnology
Xuhui Peng, Tao Chen, Ruotong Chen, Shizheng Chen, Qing Zhao, Xiaoping Huang
Summary: In this study, a novel method was proposed to design and fabricate optoelectronic devices with highly precise controlled photorefractive liquid crystal structures. By utilizing quantum dots and electric tuning, a regular periodic grating was formed in a quantum dot-doped liquid crystal volume illuminated by a laser standing evanescent wave field. The obtained optical diffraction pattern showed equally spaced light spots and high diffraction efficiency, indicating a significant change in the refractive index of the nanostructured device.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2024)
Article
Nanoscience & Nanotechnology
Kai-Hua Yang, Xiao-Hui Liang, Huai-Yu Wang, Yi-Fan Wu, Qian-Qian Yang
Summary: In this work, a theoretical model is proposed to achieve the controllability of quantum interference and decoherence. The effects of intralead Coulomb interaction, interdot tunneling, and electron-phonon interactions on differential conductance are investigated. The results show the appearance of destructive interference, Fano interference, and negative differential conductance in strong dot-lead tunneling regions, while a characteristic pattern of positive and negative differential conductances appears in the weak dot-lead tunneling regime.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2024)
Article
Nanoscience & Nanotechnology
Xueying Wang, Qian Ma, Qi Zhang, Yi Wang, Lingyu Li, Dongheng Zhao, Zhiqiang Liu
Summary: Porous double-channel alpha-Fe2O3/SnO2 heterostructures with tunable surface/interface transport mechanism were successfully fabricated by electrospinning and calcination. These heterostructures exhibited a large specific surface area, providing more active sites and enhanced adsorption capacity. The optimal composite materials showed the highest response value and the fastest response/recovery times to DMF, along with good cycling performance, long-term stability, and high gas selectivity.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2024)
Article
Nanoscience & Nanotechnology
Donglin Guo, Zhengmeng Xu, Chunhong Li, Kejian Li, Bin Shao, Xianfu Luo, Jianchun Sun, Yilong Ma
Summary: Using full electron-phonon interactions and the Boltzmann transport equation, this study investigates the phonon scattering channel and electrical properties of graphene under anharmonic phonon renormalization (APRN). The results show that the APRN reduces the phonon frequency and three-phonon phase space with increasing temperature, affecting the acoustic branch more than the optical branch. The thermal conductivity of graphene decreases after considering three- and four-phonon scattering, and the primary scattering channels are identified. Furthermore, the APRN increases the strength of electron-phonon coupling and leads to an increase in n-type electric resistance at room temperature.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2024)
Article
Nanoscience & Nanotechnology
Hongping Zhao, Man Zhao, Dayong Jiang
Summary: The study proposes a broadband photodetector with high response, high sensitivity, and controllable band by integrating quantum dots and highly conductive materials. The PD composed of ZnO film/PbS quantum dots heterostructure shows excellent photoresponse performance in the UV-Vis-NIR range, with the peak responsivity increased by 550%, accompanied by significant red shift, faster response, and recovery speed. By using RF magnetron sputtering to prepare ultra-thin ZnO film, the impact of PbS quantum dots on the photoelectric properties of ZnO film is comprehensively and systematically discussed.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2024)
Article
Nanoscience & Nanotechnology
Ye Xuan Meng, Liwei Jiang, Yisong Zheng
Summary: Manipulating magnetism by electrical means is an effective method for realizing ultra-low power spintronic-integrated circuits. In this study, it is demonstrated that the two-dimensional semiconductor material InO monolayer can be tuned to a half-metallic state by applying a gate voltage, providing theoretical guidance for adjusting two-dimensional magnetic semiconductors.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2024)
Article
Nanoscience & Nanotechnology
Anusha Kachu, Aalu Boda
Summary: In this research, we investigated the impact of confinement nature on a neutral hydrogenic donor impurity in a quantum dot. The study demonstrated intriguing behavior in response to changes in potential shape, quantum dot parameters, and spin-orbit coupling strengths. The findings provide valuable insights into the fundamental physics of quantum dots and impurities and can aid in the design and optimization of QD-based technologies.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2024)