Progress in Surface Science最新文献

{"title":"Ultrafast surface Dirac fermion dynamics of Sb2Te3-based topological insulators","authors":"Kazuki Sumida ,&nbsp;Yukiaki Ishida ,&nbsp;Jens Güdde ,&nbsp;Ulrich Höfer ,&nbsp;Shik Shin ,&nbsp;Akio Kimura","doi":"10.1016/j.progsurf.2021.100628","DOIUrl":"https://doi.org/10.1016/j.progsurf.2021.100628","url":null,"abstract":"<div><p><span>Topological insulators (TIs) characterized by gapless and spin-polarized conical band dispersion on their surfaces have been extensively studied over the last decade. This article reviews our recent works on ultrafast carrier dynamics of Sb</span>₂Te₃<span>-based nonmagnetic and magnetic TIs by utilizing state-of-the-art femtosecond time- and angle-resolved photoelectron spectroscopy. We have demonstrated that the electronic recovery time elongated from a few ps to </span><span><math><mrow><mo>&gt;</mo></mrow></math></span>400 ps in case that the Dirac point was close to the Fermi energy in the series of (<span><math><mrow><msub><mrow><mi>Sb</mi></mrow><mrow><mn>1</mn><mo>-</mo><mi>x</mi></mrow></msub></mrow></math></span><span><math><mrow><msub><mrow><mi>Bi</mi></mrow><mrow><mi>x</mi></mrow></msub></mrow></math></span>)₂Te₃. We also investigated how the magnetic-impurity affects the carrier dynamics in ferromagnetic <span><math><mrow><msub><mrow><mi>Sb</mi></mrow><mrow><mn>2</mn><mo>-</mo><mi>y</mi></mrow></msub></mrow></math></span><span><math><mrow><msub><mrow><mi>V</mi></mrow><mrow><mi>y</mi></mrow></msub></mrow></math></span>Te₃. It was found that the electronic recovery time drastically shortened from a few ps to <span><math><mrow><mo>&lt;</mo></mrow></math></span><span>500 fs with increasing vanadium concentration. Since the lifetime of the nonequilibrated surface Dirac fermions can range from femto- to nano-second, Sb</span>₂Te₃-based TIs would be promising for ultrafast spin switching and spin-polarized current generation device applications.</p></div>","PeriodicalId":416,"journal":{"name":"Progress in Surface Science","volume":"96 2","pages":"Article 100628"},"PeriodicalIF":6.4,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.progsurf.2021.100628","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"1615662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical exfoliation of large area 2D materials from vdW crystals","authors":"Fang Liu","doi":"10.1016/j.progsurf.2021.100626","DOIUrl":"https://doi.org/10.1016/j.progsurf.2021.100626","url":null,"abstract":"<div><p>Monolayer two-dimensional (2D) materials, such as graphene and transition metal dichalcogenides<span><span> (TMDCs), provide a versatile platform for exploring novel physical phenomena at the 2D limit, and show great promise for next-generation electronic, optoelectronic, and </span>quantum devices<span><span>. To overcome the weak van der Waals interaction in the bulk layered crystal and achieve high quality single-crystal monolayers is a crucial task in top-down mechanical exfoliation. Tape exfoliation has long been the dominant approach to obtain single-crystal monolayers with high quality. More recently, there has been a fast development of using metals as an intermediate to enhance monolayer area and exfoliation yield. This review will provide a survey of mechanical exfoliation strategies of tape and metal-assisted exfoliations, particularly for the most popular graphene and TMDC materials. The interfacial interaction and lateral strain between monolayer and other materials such as oxides and metals play a crucial role in monolayer </span>selectivity and yield. The challenges and opportunities will be highlighted for future development of exfoliating procedures to achieve large-area and high-quality 2D material monolayers and artificial stacks.</span></span></p></div>","PeriodicalId":416,"journal":{"name":"Progress in Surface Science","volume":"96 2","pages":"Article 100626"},"PeriodicalIF":6.4,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.progsurf.2021.100626","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"2206908","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electron and positron pair emission by low energy positron impact on surfaces","authors":"F.O. Schumann ,&nbsp;I.S. Brandt ,&nbsp;Z. Wei ,&nbsp;J. Kirschner ,&nbsp;F. Giebels ,&nbsp;H. Gollisch ,&nbsp;R. Feder","doi":"10.1016/j.progsurf.2021.100629","DOIUrl":"https://doi.org/10.1016/j.progsurf.2021.100629","url":null,"abstract":"<div><p>The emission of electron pairs from surfaces has the power to reveal details about the electron–electron interaction in condensed matter<span>. This process, stimulated by a primary electron or photon beam, has been studied both in experiment and theory over the last two decades. An additional pathway, namely positron–electron pair emission, holds the promise to provide additional information. It is based on the notion that the Pauli exclusion principle does not need to be considered for this process.</span></p><p>We have commissioned a laboratory based positron<span><span> source and performed a systematic study on a variety of solid surfaces. In a symmetric emission geometry we can explore the fact that positron and electron are distinguishable particles. Following fundamental symmetry arguments we have to expect that the available energy is shared unequally among positron and electron. Experimentally we observe such a behavior for all materials studied. We find an universal feature for all materials in the sense that on average the positron carries a larger fraction of the available energy. This is qualitatively accounted for by a simplified scattering model. Numerical results, which we obtained by a microscopic theory of positron–electron emission from surfaces, reveal however that there are also cases in which the electron carries more energy. Whether the positron or the electron is more </span>energetic<span> depends on details of the bound electron state and of the emission geometry. The coincidence intensity is strongly material dependent and there exists an almost monotonic relation between the singles and coincidence intensity. These results resemble the findings obtained in electron and photon stimulated electron pair emission. An additional reaction channel is the emission of an electron pair upon positron impact. We will discuss the energy distributions and the material dependence of the coincidence signal which shows similar features as those for positron–electron pairs.</span></span></p></div>","PeriodicalId":416,"journal":{"name":"Progress in Surface Science","volume":"96 2","pages":"Article 100629"},"PeriodicalIF":6.4,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.progsurf.2021.100629","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"1994640","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recent advances in the use of curved single crystal surfaces","authors":"Sabine V. Auras,&nbsp;Ludo B.F. Juurlink","doi":"10.1016/j.progsurf.2021.100627","DOIUrl":"https://doi.org/10.1016/j.progsurf.2021.100627","url":null,"abstract":"<div><p>In surface science, research traditionally employs macroscopically flat surfaces of single crystals. Curved surfaces have been applied more sporadically, but their history stretches back for many decades. Realization of the potential benefits and practical applications in surface physics and surface chemistry research progressed slowly in the 20th century. In more recent decades, research employing partial cylinders and dome-shaped crystals have found renewed interest. Modern surface sensitive techniques are being employed allowing the inherent large range of surface structures to reveal new insights. We briefly review the history, describe several types of surfaces and the range of structures they contain, suggest a notation for common types of curved surfaces, and discuss recent studies in more detail. We mainly focus on metal samples. We close with a short outlook.</p></div>","PeriodicalId":416,"journal":{"name":"Progress in Surface Science","volume":"96 2","pages":"Article 100627"},"PeriodicalIF":6.4,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.progsurf.2021.100627","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"1784757","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A theoretical review on the single-impurity electron spin resonance on surfaces","authors":"Fernando Delgado ,&nbsp;Nicolás Lorente","doi":"10.1016/j.progsurf.2021.100625","DOIUrl":"https://doi.org/10.1016/j.progsurf.2021.100625","url":null,"abstract":"<div><p><span>The development of electron spin resonance (ESR) combined with scanning tunneling spectroscopy (STM) is undoubtedly one of the main experimental breakthroughs in surface science of the last decade thanks to joining the extraordinarily high energy resolution of ESR (nano-eV scale) with the single-atom spatial resolution of STM (sub-Ångström scale). While the experimental results have significantly grown with the number of groups that have succeeded in implementing the technique, the physical mechanism behind it is still unclear, with several different mechanisms proposed to explain it. Here, we start by revising the main characteristics of the experimental setups and observed features. Then, we review the main theoretical proposals, with both their strengths and weaknesses. One of our conclusions is that many of the proposed mechanisms share the same basic principles, the time-dependent electric field at the STM junction is modulating the coupling of the spin-polarized </span>transport electrons with the local spin. This explains why these mechanims are essentially equivalent in a broad picture. We analyze the subtle differences between some of them and how they compare with the different experimental observations.</p></div>","PeriodicalId":416,"journal":{"name":"Progress in Surface Science","volume":"96 2","pages":"Article 100625"},"PeriodicalIF":6.4,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.progsurf.2021.100625","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"2363139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Surface transfer doping of diamond: A review","authors":"Kevin G. Crawford ,&nbsp;Isha Maini ,&nbsp;David A. Macdonald,&nbsp;David A.J. Moran","doi":"10.1016/j.progsurf.2021.100613","DOIUrl":"https://doi.org/10.1016/j.progsurf.2021.100613","url":null,"abstract":"<div><p>Ultra-wide bandgap materials show great promise as a solution to some of the limitations of current state of the art semiconductor technology. Among these, diamond has exhibited great potential for use in high-power, high-temperature electronics, as well as sensing and quantum applications. Yet, significant challenges associated with impurity doping of the constrained diamond lattice remain a primary impediment towards the development of diamond-based electronic devices. An alternative approach, used with continued success to unlock the use of diamond for semiconductor applications, has been that of ‘surface transfer doping’ - a process by which intrinsically insulating diamond surfaces can be made semiconducting without the need for traditional impurity doping. Here, we present a review of progress in surface transfer doping of diamond, both a history and current outlook of this highly exploitable attribute.</p></div>","PeriodicalId":416,"journal":{"name":"Progress in Surface Science","volume":"96 1","pages":"Article 100613"},"PeriodicalIF":6.4,"publicationDate":"2021-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.progsurf.2021.100613","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"2120187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Probing local moments in nanographenes with electron tunneling spectroscopy","authors":"R. Ortiz ,&nbsp;J. Fernández-Rossier","doi":"10.1016/j.progsurf.2020.100595","DOIUrl":"https://doi.org/10.1016/j.progsurf.2020.100595","url":null,"abstract":"<div><p>The emergence of local moments in graphene zigzag edges, grain boundaries, vacancies and sp³ defects has been widely studied theoretically. However, conclusive experimental evidence is scarce. Recent progress in on-surface synthesis has made it possible to create nanographenes, such as triangulenes, with local moments in their ground states, and to probe them using scanning tunneling microscope (STM) spectroscopy. Here we review the application of the theory of sequential and cotunneling transport to relate the <span><math><mrow><mi>dI</mi><mo>/</mo><mi>dV</mi></mrow></math></span> spectra with the spin properties of nanographenes probed by STM. This approach permits us to connect the <span><math><mrow><mi>dI</mi><mo>/</mo><mi>dV</mi></mrow></math></span><span><span> with the many-body energies and wavefunctions of the graphene nanostructures. We apply this method describing the electronic states of the nanographenes by means of exact diagonalization of the </span>Hubbard model within a restricted Active Space. This permits us to provide a proper quantum description of the emergence of local moments in graphene and its interplay with transport. We discuss the results of this theory in the case of diradical nanographenes, such as triangulene, rectangular ribbons and the Clar’s goblet, that have been recently studied experimentally by means of STM spectroscopy. This approach permits us to calculate both the </span><span><math><mrow><mi>dI</mi><mo>/</mo><mi>dV</mi></mrow></math></span> spectra, that yields excitation energies, as well as the atomically resolved conductivity maps, that provide information on the wavefunctions of the collective spin modes.</p></div>","PeriodicalId":416,"journal":{"name":"Progress in Surface Science","volume":"95 4","pages":"Article 100595"},"PeriodicalIF":6.4,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.progsurf.2020.100595","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"2620913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Scanning Kelvin Probe Force Microscopy as a means for comparative quantification of cold-rolling and visualizing the surface susceptibility to galvanic cells; compared to neutron diffraction and EBSD","authors":"Madjid Sarvghad,&nbsp;Theodore A. Steinberg,&nbsp;Geoffrey Will","doi":"10.1016/j.progsurf.2020.100594","DOIUrl":"https://doi.org/10.1016/j.progsurf.2020.100594","url":null,"abstract":"<div><p>High-Resolution Neutron Diffraction (HRND), Electron Back-Scatter Diffraction (EBSD) and Scanning Kelvin Probe Force Microscopy (SKPFM) techniques were used to comparatively characterize the surface electrical properties of Inconel 690 and stainless steel 316L alloys in cold-rolled and unrolled (annealed) conditions. Results indicated that a direct relation exists between the density of lattice defects (measured by HRND and EBSD) and heterogeneity of surface potential (measured by SKPFM). Mapping of the Volta potential and deconvolution of the corresponding histogram plots of the acquired data were utilized to visualize and comparatively quantify crystal lattice defects and estimate the surface susceptibility to the formation of micro/nano-galvanic cells. SKPFM was found as a reliable alternative to electron and neutron scattering techniques for comparative evaluation of energy states on alloys’ surfaces.</p></div>","PeriodicalId":416,"journal":{"name":"Progress in Surface Science","volume":"95 3","pages":"Article 100594"},"PeriodicalIF":6.4,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.progsurf.2020.100594","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"2067671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dielectric metasurfaces: From wavefront shaping to quantum platforms","authors":"Chuanlin Li ,&nbsp;Peng Yu ,&nbsp;Yongjun Huang ,&nbsp;Qiang Zhou ,&nbsp;Jiang Wu ,&nbsp;Zhe Li ,&nbsp;Xin Tong ,&nbsp;Qiye Wen ,&nbsp;Hao-Chung Kuo ,&nbsp;Zhiming M. Wang","doi":"10.1016/j.progsurf.2020.100584","DOIUrl":"https://doi.org/10.1016/j.progsurf.2020.100584","url":null,"abstract":"<div><p><span>Metasurfaces<span> are nanopatterned structures of sub-wavelength thickness. Their effective refractive index<span> and spectral characteristic can be tailored by material composition, intrinsic and extrinsic resonances, structure size, and ambient conditions. Consequently, they allow for phase, amplitude, polarisation, and spatial control of an optical field beyond what natural materials can offer. Dielectric metasurfaces with lower loss have opened a wide range of new applications such as enhanced imaging, structural colour, </span></span></span>holography<span><span><span>, and planar sensors. In particular, beam steering and control measures such as nonlinear </span>optics, ultrafast optics, and </span>quantum optics are of increasing importance for quantum communication, computation, and information processing. In this review, the recent progress on dielectric metasurfaces is summarised, including advanced fabrication technologies and novel applications from advanced wavefront shaping to quantum platforms. In addition, a perspective for the future development of the field is presented.</span></p></div>","PeriodicalId":416,"journal":{"name":"Progress in Surface Science","volume":"95 2","pages":"Article 100584"},"PeriodicalIF":6.4,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.progsurf.2020.100584","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"3390894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Laser-based double photoemission spectroscopy at surfaces","authors":"Cheng-Tien Chiang ,&nbsp;Andreas Trützschler ,&nbsp;Michael Huth ,&nbsp;Robin Kamrla ,&nbsp;Frank O. Schumann ,&nbsp;Wolf Widdra","doi":"10.1016/j.progsurf.2020.100572","DOIUrl":"https://doi.org/10.1016/j.progsurf.2020.100572","url":null,"abstract":"<div><p><span>The recent development of double photoemission<span> (DPE) spectroscopy at surfaces using laser-based high-order harmonic generation in combination with time-of-flight electron spectroscopy<span> is reviewed. Relevant experimental conditions including the solid angle for collecting photoelectron pairs, the energy and angular resolutions, as well as the repetition rate and the photon energy range of light sources are introduced. As examples, we provide an overview of laser-based DPE results on the </span></span></span>noble metals<span> Ag and Cu as well as transition metal oxides NiO and CoO. The DPE energy and angular distributions of photoelectron pairs are compared with emphasis on the possible indications of electron-electron interaction. Potential further developments including femtosecond time-resolved DPE experiments are outlined.</span></p></div>","PeriodicalId":416,"journal":{"name":"Progress in Surface Science","volume":"95 1","pages":"Article 100572"},"PeriodicalIF":6.4,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.progsurf.2020.100572","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"2415674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}