| Records |
| Author |
Walter, A.L.; Sahin, H.; Jeon, K.J.; Bostwick, A.; Horzum, S.; Koch, R.; Speck, F.; Ostler, M.; Nagel, P.; Merz, M.; Schupler, S.; Moreschini, L.; Chang, Y.J.; Seyller, T.; Peeters, F.M.; Horn, K.; Rotenberg, E.; |
| Title |
Luminescence, patterned metallic regions, and photon-mediated electronic changes in single-sided fluorinated graphene sheets |
Type |
A1 Journal article |
| Year |
2014 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
| Volume |
8 |
Issue |
8 |
Pages |
7801-7808 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| Abstract |
Single-sided fluorination has been predicted to open an electronic band gap in graphene and to exhibit unique electronic and magnetic properties; however, this has not been substantiated by experimental reports. Our comprehensive experimental and theoretical study of this material on a SiC(0001) substrate shows that single-sided fluorographene exhibits two phases, a stable one with a band gap of similar to 6 eV and a metastable one, induced by UV irradiation, with a band gap of similar to 2.5 eV. The metastable structure, which reverts to the stable “ground-state” phase upon annealing under emission of blue light, in our view is induced by defect states, based on the observation of a nondispersive electronic state at the top of the valence band, not unlike that found in organic molecular layers. Our structural data show that the stable C2F ground state has a “boat” structure, in agreement with our X-ray magnetic circular dichroism data, which show the absence of an ordered magnetic phase. A high flux of UV or X-ray photons removes the fluorine atoms, demonstrating the possibility of lithographically patterning conducting regions into an otherwise semiconducting 2D material. |
| Address |
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| Corporate Author |
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Thesis  |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000340992300025 |
Publication Date |
2014-08-09 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1936-0851;1936-086X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
13.942 |
Times cited |
23 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 13.942; 2014 IF: 12.881 |
| Call Number |
UA @ lucian @ c:irua:119263 |
Serial |
1857 |
| Permanent link to this record |
| |
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| |
| Author |
Sanchez-Barriga, J.; Ogorodnikov, I.I.; Kuznetsov, M.V.; Volykhov, A.A.; Matsui, F.; Callaert, C.; Hadermann, J.; Verbitskiy, N.I.; Koch, R.J.; Varykhalov, A.; Rader, O.; Yashina, L.V. |
| Title |
Observation of hidden atomic order at the interface between Fe and topological insulator Bi2Te3 |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
| Volume |
19 |
Issue |
45 |
Pages |
30520-30532 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
<script type='text/javascript'>document.write(unpmarked('To realize spintronic devices based on topological insulators (TIs), well-defined interfaces between magnetic metals and TIs are required. Here, we characterize atomically precisely the interface between the 3d transition metal Fe and the TI Bi2Te3 at different stages of its formation. Using photoelectron diffraction and holography, we show that after deposition of up to 3 monolayers Fe on Bi2Te3 at room temperature, the Fe atoms are ordered at the interface despite the surface disorder revealed by our scanning-tunneling microscopy images. We find that Fe occupies two different sites: a hollow adatom deeply relaxed into the Bi2Te3 quintuple layers and an interstitial atom between the third (Te) and fourth (Bi) atomic layers. For both sites, our core-level photoemission spectra and density-functional theory calculations demonstrate simultaneous chemical bonding of Fe to both Te and Bi atoms. We further show that upon deposition of Fe up to a thickness of 20 nm, the Fe atoms penetrate deeper into the bulk forming a 2-5 nm interface layer containing FeTe. In addition, excessive Bi is pushed down into the bulk of Bi2Te3 leading to the formation of septuple layers of Bi3Te4 within a distance of similar to 25 nm from the interface. Controlling the magnetic properties of the complex interface structures revealed by our work will be of critical importance when optimizing the efficiency of spin injection in TI-based devices.')); |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
Cambridge |
Editor |
|
| Language |
|
Wos |
000416054400023 |
Publication Date |
2017-10-24 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1463-9076; 1463-9084 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.123 |
Times cited |
4 |
Open Access |
OpenAccess |
| Notes |
; The authors acknowledge financial support within the bilateral program “Russian-German Laboratory at BESSY II” and thank Helmholtz Zentrum Berlin for granting access to the beamlines RGBL, UE112-PGM2a and U49-PGM1. The Supercomputing Center of Lomonosov Moscow State University is gratefully acknowledged for granting access to the “Lomonosov” supercomputer. The work was partially supported by DFG priority program SPP 1666, Impuls- und Vernetzungsfonds der Helmholtz-Gemeinschaft (Grant No. HRJRG-408) and Russian Foundation for Basic Research (Grants No. 13-02-91327 and No. 16-29-06410). C. C. acknowledges support from the University of Antwerp through the BOF grant 31445. The authors thank Dr Vera Neudachina, Daria Tsukanova, Dr Elmar Kataev and Dr Maria Batuk for their support during the XPS and TEM experiments. ; |
Approved |
Most recent IF: 4.123 |
| Call Number |
UA @ lucian @ c:irua:147659 |
Serial |
4888 |
| Permanent link to this record |
