A. Usui

913 total citations
24 papers, 745 citations indexed

About

A. Usui is a scholar working on Condensed Matter Physics, Materials Chemistry and Atomic and Molecular Physics, and Optics. According to data from OpenAlex, A. Usui has authored 24 papers receiving a total of 745 indexed citations (citations by other indexed papers that have themselves been cited), including 20 papers in Condensed Matter Physics, 12 papers in Materials Chemistry and 10 papers in Atomic and Molecular Physics, and Optics. Recurrent topics in A. Usui's work include GaN-based semiconductor devices and materials (19 papers), ZnO doping and properties (12 papers) and Semiconductor Quantum Structures and Devices (9 papers). A. Usui is often cited by papers focused on GaN-based semiconductor devices and materials (19 papers), ZnO doping and properties (12 papers) and Semiconductor Quantum Structures and Devices (9 papers). A. Usui collaborates with scholars based in Japan, Sweden and United States. A. Usui's co-authors include Haruo Sunakawa, Yuichi Oshima, Takeshi Eri, Toshinari Ichihashi, Masatomo Shibata, G. D. Watkins, M. Mizuta, Kenji Kobayashi, K. H. Chow and T. Paskova and has published in prestigious journals such as Physical Review Letters, Physical review. B, Condensed matter and Journal of Applied Physics.

In The Last Decade

A. Usui

24 papers receiving 730 citations

Peers — A (Enhanced Table)

Peers by citation overlap · career bar shows stage (early→late) cites · hero ref

Name h Career Trend Papers Cites
A. Usui Japan 11 644 365 334 334 184 24 745
Satoru Nagao Japan 10 623 1.0× 364 1.0× 340 1.0× 348 1.0× 263 1.4× 21 786
A. S. Usikov Russia 13 638 1.0× 359 1.0× 319 1.0× 290 0.9× 198 1.1× 45 737
V. M. Phanse United States 10 579 0.9× 255 0.7× 323 1.0× 275 0.8× 260 1.4× 14 708
W. G. Perry United States 13 803 1.2× 348 1.0× 335 1.0× 376 1.1× 248 1.3× 27 897
Takeshi Eri Japan 8 491 0.8× 247 0.7× 248 0.7× 246 0.7× 103 0.6× 8 521
Y.P. Hsu Taiwan 17 577 0.9× 215 0.6× 307 0.9× 379 1.1× 207 1.1× 24 700
S.J. Chang Taiwan 16 612 1.0× 298 0.8× 417 1.2× 342 1.0× 220 1.2× 48 812
Muneyoshi Suita Japan 16 702 1.1× 390 1.1× 557 1.7× 245 0.7× 210 1.1× 38 840
S. K. Lee South Korea 10 504 0.8× 270 0.7× 251 0.8× 241 0.7× 144 0.8× 13 552
Kensaku Motoki Japan 6 559 0.9× 284 0.8× 245 0.7× 257 0.8× 160 0.9× 6 603

Countries citing papers authored by A. Usui

Since Specialization
Citations

This map shows the geographic impact of A. Usui's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by A. Usui with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites A. Usui more than expected).

Fields of papers citing papers by A. Usui

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by A. Usui. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by A. Usui. The network helps show where A. Usui may publish in the future.

Co-authorship network of co-authors of A. Usui

This figure shows the co-authorship network connecting the top 25 collaborators of A. Usui. A scholar is included among the top collaborators of A. Usui based on the total number of citations received by their joint publications. Widths of edges represent the number of papers authors have co-authored together. Node borders signify the number of papers an author published with A. Usui. A. Usui is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

20 of 20 papers shown
1.
Ḿonemar, B., T. Paskova, J. P. Bergman, et al.. (2010). Transient photoluminescence of shallow donor bound excitons in GaN. Physical Review B. 82(23). 34 indexed citations
2.
Monemar, B., T. Paskova, Г. Позина, et al.. (2009). Evidence for Two Mg Related Acceptors in GaN. Physical Review Letters. 102(23). 235501–235501. 108 indexed citations
3.
Ḿonemar, B., T. Paskova, J. P. Bergman, et al.. (2008). Recombination of free and bound excitons in GaN. physica status solidi (b). 245(9). 1723–1740. 93 indexed citations
4.
Торопов, А. А., Yu. É. Kitaev, T. V. Shubina, et al.. (2008). Polarization-resolved phonon-assisted optical transitions of bound excitons in wurtzite GaN. Physical Review B. 77(19). 5 indexed citations
5.
Ḿonemar, B., T. Paskova, J. P. Bergman, et al.. (2007). Recombination dynamics of free and bound excitons in bulk GaN. Superlattices and Microstructures. 43(5-6). 610–614. 3 indexed citations
6.
Darakchieva, Vanya, et al.. (2007). Lattice parameters of bulk GaN fabricated by halide vapor phase epitaxy. Journal of Crystal Growth. 310(5). 959–965. 17 indexed citations
7.
8.
Johannesen, P., A. Żakrzewski, L. S. Vlasenko, et al.. (2004). Intrinsic defects in GaN. II. Electronically enhanced migration of interstitial Ga observed by optical detection of electron paramagnetic resonance. Physical Review B. 69(4). 13 indexed citations
9.
Oshima, Yuichi, Takeshi Eri, Masatomo Shibata, et al.. (2003). Preparation of Freestanding GaN Wafers by Hydride Vapor Phase Epitaxy with Void-Assisted Separation. Japanese Journal of Applied Physics. 42(Part 2, No.1A/B). L1–L3. 232 indexed citations
10.
Watkins, G. D., K. H. Chow, P. Johannesen, et al.. (2003). Intrinsic defects in GaN: what we are learning from magnetic resonance studies. Physica B Condensed Matter. 340-342. 25–31. 5 indexed citations
11.
Usui, A., et al.. (2002). Role of TiN Film in the Fabrication of Freestanding GaN Wafers Using Hydride Vapor Phase Epitaxy with Void-Assisted Separation. physica status solidi (a). 194(2). 572–575. 33 indexed citations
12.
Jiang, Fan, et al.. (2001). Hydrogen vibrational lines in HVPE GaN. Physica B Condensed Matter. 308-310. 122–125. 3 indexed citations
13.
Yonenaga, Ichiro, et al.. (2000). High Temperature Hardness of Bulk Single Crystal GaN. MRS Internet Journal of Nitride Semiconductor Research. 5(S1). 343–348. 4 indexed citations
14.
Yonenaga, Ichiro, et al.. (1999). High Temperature Hardness of Bulk Single Crystal GaN. MRS Proceedings. 595. 3 indexed citations
15.
Kimura, A., Chiaki Sasaoka, Akira Sakai, & A. Usui. (1997). Wide Gan Stripes by Lateral Growth in Metalorganic Vapor Phase Epitaxy. MRS Proceedings. 482. 6 indexed citations
16.
Usui, A., et al.. (1996). Theoretical gain of [hhk]-oriented quantum wire lasers. Journal of Applied Physics. 79(6). 3340–3342. 2 indexed citations
17.
Mochizuki, Yuji, Toshikazu Takada, Chiaki Sasaoka, et al.. (1994). Theoretical study ofAs2desorption from the Ga dangling-bond site. Physical review. B, Condensed matter. 49(7). 4658–4667. 11 indexed citations
18.
Usui, A., et al.. (1985). Low threshold current operation of vapour-grown 650 nm-band InGaAsP/InGaP DH lasers. Electronics Letters. 21(2). 54–56. 12 indexed citations
19.
Inoshita, Takeshi & A. Usui. (1984). Raman Scattering in InGaAsP Lattice-Matched to GaAs. Japanese Journal of Applied Physics. 23(3A). L135–L135. 1 indexed citations
20.
Usui, A. & Katsumi Mori. (1976). Surface Defects of GaP Epitaxial Layers Grown by Ga–PCl3–H2System. Japanese Journal of Applied Physics. 15(11). 2245–2246. 1 indexed citations

Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive bibliographic database. While OpenAlex provides broad and valuable coverage of the global research landscape, it—like all bibliographic datasets—has inherent limitations. These include incomplete records, variations in author disambiguation, differences in journal indexing, and delays in data updates. As a result, some metrics and network relationships displayed in Rankless may not fully capture the entirety of a scholar's output or impact.

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