Article
Chemistry, Physical
G. Ambrosio, S. Achilli, S. Pagliara
Summary: This study aims to clarify the characteristics of the n=1 image potential state of graphene on SiC through nonlinear photoemission experiments. Compared to graphene grown on metallic substrates, graphene on SiC exhibits a broader image state, which may be related to a second image state or the image states predicted for free-standing graphene.
Article
Materials Science, Multidisciplinary
Y. W. Sun, D. Holec, D. Gehringer, L. Li, O. Fenwick, D. J. Dunstan, C. J. Humphreys
Summary: Density functional theory was used to study the properties of graphene on different orientations of silicon substrates. It was found that covalent bonds can form between graphene and silicon atoms, and the different orientations of the silicon substrate have a significant effect on the electron density and work function of graphene. These findings provide valuable guidance for the growth of graphene on silicon for electronic devices.
Article
Optics
Jingshu Guo, Chaoyue Liu, Laiwen Yu, Hengtai Xiang, Yuluan Xiang, Daoxin Dai
Summary: Graphene-silicon-graphene waveguide photodetectors operating at wavelengths of 1.55 and 2 μm are demonstrated with potential for large-scale integration. The photodetectors exhibit high bandwidth, ultra-low dark current, high photo-to-dark current ratio, and high linear dynamic range.
LASER & PHOTONICS REVIEWS
(2023)
Article
Chemistry, Physical
Jianyi Liu, Xiang Jiang, Xintong Li, Xiaochuan Ma, Xia Sun, Qijing Zheng, Xuefeng Cui, Shijing Tan, Jin Zhao, Bing Wang
Summary: The study reveals that IPS on the 2H-MoS2 surface exhibits nearly free-electron characteristics, with unique behaviors in terms of electron lifetime and photoexcitation.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Chemistry, Multidisciplinary
Vyacheslav M. Silkin, Eugene Kogan, Godfrey Gumbs
Summary: In this study, the response of a free-standing graphene sheet to an external perpendicular static electric field was investigated using first-principles. The charge density distribution near the graphene monolayer caused by the electric field was determined, and a new set of energies for image-potential states was generated using the determined centroid of the extra density induced by the electric field.
Article
Materials Science, Multidisciplinary
Y. Zhao, T. Suzuki, T. Iimori, H-W Kim, J. R. Ahn, M. Horio, Y. Sato, Y. Fukaya, T. Kanai, K. Okazaki, S. Shin, S. Tanaka, F. Komori, H. Fukidome, I Matsuda
Summary: The carrier dynamics in various types of epitaxial graphene layers on SiC substrates were studied using TARPES. Layer-dependent electron doping was observed in the Dirac bands of quasicrystalline bilayer graphene, resulting in the generation of transient voltage between the upper and lower layers. The amount of photoinduced carrier transport depends on the distance from the substrate. Comparison of TARPES results between flat and stepped SiC substrates suggests that the doping carriers likely originate from interface step states.
Article
Chemistry, Physical
Shivi Rathore, Dinesh Kumar Patel, Mukesh Kumar Thakur, Golam Haider, Martin Kalbac, Mattias Kruskopf, Chieh- Liu, Albert F. Rigosi, Randolph E. Elmquist, Chi-Te Liang, Po-Da Hong
Summary: Epitaxial graphene (EG) on 4H-SiC with an interfacial buffer layer (IBL) shows improved photoresponsivity, enabling positive and negative photoresponses for different laser excitations. The broadband binary photoresponse is mainly due to the energy band alignment at the IBL/EG interface and the sensitive work function of EG, resulting in a photoresponsivity of >10 A/W under certain conditions. These results pave the way for selective light-triggered logic devices based on EG and open new possibilities for broadband photodetection.
Article
Chemistry, Physical
Yuji Hamamoto, Hiroyuki Sawada, Sasfan Arman Wella, Kouji Inagaki, Ikutaro Hamada, Yoshitada Morikawa
Summary: The structural and electronic properties of lead phthalocyanine (PbPc) adsorbed on graphene are studied theoretically using the van der Waals density functional method. It is found that an extended state similar to an image potential state (IPS) emerges in a close-packed PbPc monolayer, hybridizing with the lowest IPS of graphene to form bonding and antibonding states at the PbPc-graphene interface. The effective masses of the hybrid IPSs are increased due to the adsorption of PbPc.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Review
Chemistry, Multidisciplinary
Gunendra Prasad Ojha, Gun Woong Kang, Yun-Su Kuk, Ye Eun Hwang, Oh Hoon Kwon, Bishweshwar Pant, Jiwan Acharya, Yong Wan Park, Mira Park
Summary: Silicon carbide (SiC) is a highly promising carbide material known for its applications in electrochemical supercapacitors, photocatalysis, microwave absorption, field-effect transistors, and sensors. It offers advantages such as high thermal stability, chemical stability, thermal conductivity, and mechanical behavior, making it a potential candidate in various fields. This review focuses on the synthesis techniques and properties of nanostructured SiC (0D, 1D, 2D, and 3D), as well as the current research trends in electrochemical supercapacitor electrodes. The review also highlights future research directions, key obstacles, and possible solutions.
Article
Multidisciplinary Sciences
Vladimir S. Prudkovskiy, Yiran Hu, Kaimin Zhang, Yue Hu, Peixuan Ji, Grant Nunn, Jian Zhao, Chenqian Shi, Antonio Tejeda, David Wander, Alessandro De Cecco, Clemens B. Winkelmann, Yuxuan Jiang, Tianhao Zhao, Katsunori Wakabayashi, Zhigang Jiang, Lei Ma, Claire Berger, Walt A. de Heer
Summary: This study demonstrates that annealed edges in conventionally patterned graphene grown on a silicon carbide substrate are stabilized and support a protected edge state. The edge state has a long mean free path and involves a non-degenerate zero-energy quasiparticle.
NATURE COMMUNICATIONS
(2022)
Article
Physics, Multidisciplinary
Junjie Chen, Baofang Liu
Summary: This study investigates the thermal conductivity of graphene nanoribbons, exploring the edge-scattering effects and the transition from diffusive to ballistic transport as dimensions decrease. Structural and dimensional design can effectively enhance phonon transport and approach theoretical limits.
EUROPEAN PHYSICAL JOURNAL PLUS
(2021)
Article
Chemistry, Multidisciplinary
Teresa Crisci, Luigi Moretti, Maurizio Casalino
Summary: The study investigates the responsivity/NEP trade-off in graphene/semiconductor Schottky photodetectors in the near-infrared regime at room temperature. The analysis shows that the ratio is influenced by the Schottky barrier height of the junction, with a closed analytical formula derived for maximizing it. Optimization methods for different semiconductors are discussed, with specific examples of optimized PDs for silicon and germanium at different wavelengths.
APPLIED SCIENCES-BASEL
(2021)
Article
Chemistry, Physical
Erhui Zhang, Mengqi Yang, Yongsheng Zhou, Xiang Ke, Jing Tang, Jiahao Guo, Zirong Li
Summary: This study successfully fabricated a graphene-based porous membrane and utilized its synergistic advantages with silicon-oxy-carbide (SiOC) to prepare a flexible all-solid-state symmetric supercapacitor (ASSSs). Compared to traditional capacitors, this device exhibits higher power density and energy density, with potential applications in flexible energy storage devices.
APPLIED SURFACE SCIENCE
(2024)
Article
Chemistry, Physical
Dominike P. de Andrade Deus, Joao Marcelo J. Lopes, Roberto H. Miwa
Summary: Heterostructures based on the stacking of graphene and hexagonal boron nitride (h-BN) on SiC(0001) substrate have been studied theoretically. The results show that h-BN encapsulation is energetically preferred below a single layer of graphene, leading to G/h-BN/SiC for bilayer systems and G/h-BN/G/SiC for trilayer systems. The electronic structure calculations reveal the preservation of graphene linear energy band dispersion in the bilayer systems, while the trilayer systems exhibit stacking-order-dependent electronic structures. Structural characterizations of these heterostructures were performed using simulations of core-level-shift and XANES spectroscopy, aiming to assist future experimental studies.
Article
Quantum Science & Technology
Vivek Vashist, Megha Khokhar, Faraz A. Inam, Rajesh V. Nair
Summary: This study investigates the enhancement of the emission rate from a single silicon-vacancy center in a SiC metasurface. By optimizing the metasurface structure, a high emission rate at a wavelength of 862 nm is achieved, providing a new approach for on-demand single-photon sources and efficient spin-photon interfaces.
ADVANCED QUANTUM TECHNOLOGIES
(2023)
Article
Chemistry, Multidisciplinary
Oskar Schuster, Peter Wientjes, Shreetu Shrestha, Ievgen Levchuk, Mykhailo Sytnyk, Gebhard J. Matt, Andres Osvet, Miroslaw Batentschuk, Wolfgang Heiss, Christoph J. Brabec, Thomas Fauster, Daniel Niesner
Article
Physics, Multidisciplinary
Maximilian Unzelmann, Hendrik Bentmann, Philipp Eck, Tilman Kisslinger, Begmuhammet Geldiyev, Janek Rieger, Simon Moser, Raphael C. Vidal, Katharina Kissner, Lutz Hammer, M. Alexander Schneider, Thomas Fauster, Giorgio Sangiovanni, Domenico Di Sante, Friedrich Reinert
PHYSICAL REVIEW LETTERS
(2020)
Article
Chemistry, Physical
Can Wang, Ruimei Wang, Jakob Hauns, Thomas Fauster
JOURNAL OF PHYSICAL CHEMISTRY C
(2020)
Article
Physics, Condensed Matter
Jieru Li, Daniel Niesner, Thomas Fauster
Summary: Thick adamantane films on Cu(111) demonstrate a negative electron affinity and a band gap, while thinner films exhibit close-to-zero electron affinity and a shift in valence bands towards the Fermi energy due to charge transfer from Cu 3d bands.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2021)
Article
Materials Science, Multidisciplinary
Maximilian Ammon, Sara Baumann, Tilman Kisslinger, Janek Rieger, Thomas Fauster, Josef Redinger, Lutz Hammer, M. Alexander Schneider
Summary: Epitaxial cobalt(II) oxide films with wurtzite crystal structure were grown on Au(111) substrates, allowing for analysis of their structural and electronic properties using surface-science methods. Experimental analysis showed excellent agreement with theoretical calculations, providing insight into the semiconducting nature of the films and predicting surface states within the bandgap.
PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS
(2021)
Article
Physics, Condensed Matter
Rebecca Helmreich, Andrej Classen, Thomas Fauster
Summary: Epitaxial MgO films on Ag(100) were investigated using photoelectron spectroscopy. Negative electron affinity of about -0.9 eV was obtained from the low-energy region of the spectra. Despite the absence of potential barrier on the surface, quantum-well resonances were observed in the lowest conduction band. The results of this study are in good agreement with theoretical calculations and provide insight into the observation of image-potential states on MgO films.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2022)
Article
Nanoscience & Nanotechnology
Lukas Schmidt-Mende, Vladimir Dyakonov, Selina Olthof, Feray uenlue, Khan Moritz Trong Le, Sanjay Mathur, Andrei D. Karabanov, Doru C. Lupascu, Laura M. Herz, Alexander Hinderhofer, Frank Schreiber, Alexey Chernikov, David A. Egger, Oleksandra Shargaieva, Caterina Cocchi, Eva Unger, Michael Saliba, Mahdi Malekshahi Byranvand, Martin Kroll, Frederik Nehm, Karl Leo, Alex Redinger, Julian Hoecker, Thomas Kirchartz, Jonathan Warby, Emilio Gutierrez-Partida, Dieter Neher, Martin Stolterfoht, Uli Wuerfel, Moritz Unmuessig, Jan Herterich, Clemens Baretzky, John Mohanraj, Mukundan Thelakkat, Clement Maheu, Wolfram Jaegermann, Thomas Mayer, Janek Rieger, Thomas Fauster, Daniel Niesner, Fengjiu Yang, Steve Albrecht, Thomas Riedl, Azhar Fakharuddin, Maria Vasilopoulou, Yana Vaynzof, Davide Moia, Joachim Maier, Marius Franckevicius, Vidmantas Gulbinas, Ross A. Kerner, Lianfeng Zhao, Barry P. Rand, Nadja Glueck, Thomas Bein, Fabio Matteocci, Luigi Angelo Castriotta, Aldo Di Carlo, Matthias Scheffler, Claudia Draxl
Summary: Metal halide perovskites are a new type of solution processed semiconductors that can compete with traditional semiconductors in functionality, especially in optoelectronic devices. Despite breakthroughs, challenges remain in terms of stability, reproducibility, and toxicity.
Article
Chemistry, Physical
Rebecca Helmreich, Thomas Fauster
Summary: The molecular orbitals of MgTPP deposited on epitaxial MgO films on Ag (100) were investigated using ultraviolet photoelectron spectroscopy and two-photon photoemission. The energy levels of the electronic states were found to be pinned to the vacuum level, and the band gap was determined to be 3.88 +/- 0.07 eV, which was largely independent of the thickness of the MgO layer.
Article
Materials Science, Multidisciplinary
Janek Rieger, Tilman Kisslinger, Andreas Raabgrund, Jonas Hauner, Daniel Niesner, Thomas Fauster, M. Alexander Schneider
Summary: Metal-halide perovskite (MHP) thin films with desired surface properties are crucial for high-efficiency solar cells. This study demonstrates the epitaxial growth of CsPbBr3 and CsSnBr3 MHPs on Au(001) substrate, resulting in purely (001)-oriented films with controlled surface terminations. The work function of the PbBr2-terminated surface is increased by 0.7 eV, leading to significant implications for MHP interface level alignment.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Janek Rieger, Jonas Hauner, Daniel Niesner, Thomas Fauster
Summary: We investigated the carrier dynamics and diffusion in metal-halide perovskites using time-resolved photoelectron spectroscopy. The results showed that surfaces and interfaces play a crucial role in modifying carrier dynamics by interface band bending and recombination. We measured electron mobilities in CsPbBr3(001) and CsSnBr3(001) films at room temperature to be 31 +/- 6 and 13 +/- 1 cm2 V-1 s-1, respectively. The mobility in CsPbBr3(001) increased to 200 +/- 8 cm2 V-1 s-1 at 90 K, indicating strong electron-phonon coupling.
Article
Materials Science, Multidisciplinary
Tilman Kisslinger, Andreas Raabgrund, Begmuhammet Geldiyev, Maximilian Ammon, Janek Rieger, Jonas Hauner, Lutz Hammer, Thomas Fauster, M. Alexander Schneider
