A. Usui

913 citations

24 papers · 745 indexed · h-index 11

Impact in

Condensed Matter Physics top 2%
- GaN-based semiconductor devices and materials
Electronic, Optical and Magnetic Materials top 10%
- Ga2O3 and related materials

Papers in ⓘ

Condensed Matter Physics 20
- GaN-based semiconductor devices and materials 19
Electronic, Optical and Magnetic Materials 9
- Ga2O3 and related materials 9

Co-authors: Haruo Sunakawa (6 shared papers)Takeshi Eri (2 shared papers)Yuichi Oshima (2 shared papers)M. Mizuta (6 shared papers)Toshinari Ichihashi (1 shared paper)Masatomo Shibata (1 shared paper)G. D. Watkins (5 shared papers)Kenji Kobayashi (1 shared paper)
Journals: Physical Review B (5 papers)Japanese Journal of Applied Physics (3 papers)Physica B Condensed Matter (2 papers)Physical Review Letters (2 papers)MRS Internet Journal of Nitride Semiconductor Research (1 paper)
Partner nations: Japan Sweden United States

In The Last Decade

A. Usui

24 papers receiving 730 citations

Peers

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-authors

The 25 scholars most cited alongside A. Usui, linked wherever they have co-authored with each other. Click a name or a connecting line to browse the papers they share.

Border = papers with A. Usui Line = papers co-authored together A. Usui links everyone, so they are left out of the graph.

All Works

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20 of 20 papers shown

Showing the 20 most-cited of 24 papers — load more, or switch the sort, to bring in the rest.

#	Work
1	Preparation of Freestanding GaN Wafers by Hydride Vapor Phase Epitaxy with Void-Assisted Separation Japanese Journal of Applied Physics ·Yuichi Oshima, Takeshi Eri, Masatomo Shibata, Haruo Sunakawa, Kenji Kobayashi, Toshinari Ichihashi, A. Usui	2003	232
2	Evidence for Two Mg Related Acceptors in GaN Physical Review Letters ·B. Monemar, T. Paskova, Г. Позина, Carl Hemmingsson, J. P. Bergman, T. Kawashima, Hiroshi Amano, Isamu Akasaki, S. Figge, D. Hommel, A. Usui	2009	108
3	Detection of Interstitial Ga in GaN Physical Review Letters ·K. H. Chow, G. D. Watkins, A. Usui, M. Mizuta	2000	103
4	Recombination of free and bound excitons in GaN physica status solidi (b) ·B. Ḿonemar, T. Paskova, J. P. Bergman, А. А. Торопов, T. V. Shubina, T. Malinauskas, A. Usui	2008	93
5	Intrinsic defects in GaN. I. Ga sublattice defects observed by optical detection of electron paramagnetic resonance Physical Review B ·K. H. Chow, L. S. Vlasenko, P. Johannesen, Cornel Bozdog, G. D. Watkins, A. Usui, Haruo Sunakawa, Chiaki Sasaoka, M. Mizuta	2004	39
6	Transient photoluminescence of shallow donor bound excitons in GaN Physical Review B ·B. Ḿonemar, T. Paskova, J. P. Bergman, Г. Позина, А. А. Торопов, T. V. Shubina, T. Malinauskas, A. Usui	2010	34
7	Role of TiN Film in the Fabrication of Freestanding GaN Wafers Using Hydride Vapor Phase Epitaxy with Void-Assisted Separation physica status solidi (a) ·A. Usui, T. Ichihashi, K. Kobayashi, Haruo Sunakawa, Yuichi Oshima, Takeshi Eri, M. Shibata	2002	33
8	Lattice parameters of bulk GaN fabricated by halide vapor phase epitaxy Journal of Crystal Growth ·Vanya Darakchieva, B. Ḿonemar, A. Usui, M. F. Saenger, M. Schubert	2007	17
9	Intrinsic defects in GaN. II. Electronically enhanced migration of interstitial Ga observed by optical detection of electron paramagnetic resonance Physical Review B ·P. Johannesen, A. Żakrzewski, L. S. Vlasenko, G. D. Watkins, A. Usui, Haruo Sunakawa, M. Mizuta	2004	13
10	Low threshold current operation of vapour-grown 650 nm-band InGaAsP/InGaP DH lasers Electronics Letters ·A. Usui, Takashi Matsumoto, M. Inai, I. Mito, K. Kobayashi, H. Watanbe	1985	12
11	Theoretical study ofAs2desorption from the Ga dangling-bond site Physical review. B, Condensed matter ·Yuji Mochizuki, Toshikazu Takada, Chiaki Sasaoka, A. Usui, Eisaku Miyoshi, Yoshiko Sakai	1994	11
12	Optical signatures of dopants in GaN Materials Science in Semiconductor Processing ·B. Ḿonemar, T. Paskova, J. P. Bergman, А. А. Торопов, T. V. Shubina, S. Figge, D. Hommel, A. Usui, Motoaki Iwaya, Satoshi Kamiyama, Hiroshi Amano, Isamu Akasaki	2006	8
13	Wide Gan Stripes by Lateral Growth in Metalorganic Vapor Phase Epitaxy MRS Proceedings ·A. Kimura, Chiaki Sasaoka, Akira Sakai, A. Usui	1997	6
14	Intrinsic defects in GaN: what we are learning from magnetic resonance studies Physica B Condensed Matter ·G. D. Watkins, K. H. Chow, P. Johannesen, L. S. Vlasenko, Cornel Bozdog, A. Żakrzewski, M. Mizuta, Haruo Sunakawa, Naotaka Kuroda, A. Usui	2003	5
15	Polarization-resolved phonon-assisted optical transitions of bound excitons in wurtzite GaN Physical Review B ·А. А. Торопов, Yu. É. Kitaev, T. V. Shubina, T. Paskova, J. P. Bergman, B. Ḿonemar, A. Usui	2008	5
16	Radiation-induced defects in GaN Physica Scripta ·Nguyên Tiên Són, Carl Hemmingsson, N. Morishita, Takeshi Ohshima, T. Paskova, K. R. Evans, A. Usui, Junichi Isoya, B. Ḿonemar, Erik Janzén	2010	5
17	Publisher’s Note: Intrinsic defects in GaN. I. Ga sublattice defects observed by optical detection of electron paramagnetic resonance [Phys. Rev. B69, 045207 (2004)] Physical Review B ·K. H. Chow, L. S. Vlasenko, P. Johannesen, Cornel Bozdog, G. D. Watkins, A. Usui, Haruo Sunakawa, Chiaki Sasaoka, M. Mizuta	2004	4
18	High Temperature Hardness of Bulk Single Crystal GaN MRS Internet Journal of Nitride Semiconductor Research ·Ichiro Yonenaga, T. Hoshi, A. Usui	2000	4
19	Recombination dynamics of free and bound excitons in bulk GaN Superlattices and Microstructures ·B. Ḿonemar, T. Paskova, J. P. Bergman, А. А. Торопов, T. V. Shubina, A. Usui	2007	3
20	Hydrogen vibrational lines in HVPE GaN Physica B Condensed Matter ·M.G. Weinstein, Fan Jiang, Michael Stavola, B. Bech Nielsen, A. Usui, M. Mizuta	2001	3

About A. Usui

A. Usui is a scholar working on Condensed Matter Physics, Electronic, Optical and Magnetic Materials, Atomic and Molecular Physics, and Optics, Materials Chemistry and Mechanics of Materials, having authored 24 papers that have together received 745 indexed citations. Recurring topics across this work include GaN-based semiconductor devices and materials (19 papers), ZnO doping and properties (12 papers), Semiconductor Quantum Structures and Devices (9 papers), Ga2O3 and related materials (9 papers), Semiconductor materials and devices (5 papers), Metal and Thin Film Mechanics (4 papers), Semiconductor Lasers and Optical Devices (2 papers) and Quantum and electron transport phenomena (1 paper). The work is most often cited by research in Condensed Matter Physics (644 citations), Electronic, Optical and Magnetic Materials (365 citations), Materials Chemistry (334 citations), Atomic and Molecular Physics, and Optics (184 citations) and Electrical and Electronic Engineering (334 citations). A. Usui has collaborated with scholars based in Japan, Sweden and United States. Frequent co-authors include Haruo Sunakawa, Takeshi Eri, Yuichi Oshima, M. Mizuta, Toshinari Ichihashi, Masatomo Shibata, G. D. Watkins, Kenji Kobayashi, K. H. Chow and T. Paskova. Their work appears in journals such as Physical Review B, Japanese Journal of Applied Physics, Physica B Condensed Matter, Physical Review Letters and MRS Internet Journal of Nitride Semiconductor Research.

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