The Japanese Journal of Applied Physics (JJAP) is an international journal for the advancement and dissemination of knowledge in all fields of applied physics. The journal publishes articles dealing with the applications of physical principles as well as articles concerning the understanding of physics that have particular applications in mind. It is published by IOP Publishing Ltd on behalf of the Japan Society of Applied Physics (JSAP).
This publication is partially supported by a Grant-in-Aid for Publication of Scientific Research Results from the Japan Society for the Promotion of Science.
The Japan Society of Applied Physics (JSAP) is pleased to announce that the Creative Commons license "CC BY" will be applied to Open Select articles to be published in Applied Physics Express (APEX) and Japanese Journal of Applied Physics (JJAP). In accordance with the policy, the copyright of Open Select articles shall belong to the authors. This policy may be retroactively applied to existing Open Select articles from July 10, 2015 with the authors' agreement.
JJAP is celebrating an increase in Impact Factor to 1.127. With an increase of 7%, there has never been a better time to publish in JJAP. To see some of our outstanding papers, please see our Spotlights
JJAP publishes a number of Special Issues each year. These feature research articles presented at major international conferences. These articles are fully peer-reviewed to JJAP's usual acceptance criteria. Thriteen special issues are planned for 2015. Click here for a list of the 2015 Special Issues.
Congratulations to Isamu Akasaki, Hiroshi Amano and Shuji Nakamura on being awarded the 2014 Nobel Prize for Physics. Several of the key papers cited by the Nobel committee were published in this journal - visit the 2014 Nobel collection to read them for free.
From 2014, JJAP will be published by IOP Publishing on behalf of The Japan Society of Applied Physics. All submissions and refereeing will continue to be handled by the JJAP Editorial Office at The Japan Society of Applied Physics. To submit a paper to JJAP, please connect to the editorial website.
In the last 30 days
Marius Chyasnavichyus et al 2015 Jpn. J. Appl. Phys. 54 08LA02
Probing of micro- and nanoscale mechanical properties of soft materials with atomic force microscopy (AFM) gives essential information about the performance of the nanostructured polymer systems, natural nanocomposites, ultrathin coatings, and cell functioning. AFM provides efficient and is some cases the exclusive way to study these properties nondestructively in controlled environment. Precise force control in AFM methods allows its application to variety of soft materials and can be used to go beyond elastic properties and examine temperature and rate dependent materials response. In this review, we discuss experimental AFM methods currently used in the field of soft nanostructured composites and biomaterials. We discuss advantages and disadvantages of common AFM probing techniques, which allow for both qualitative and quantitative mappings of the elastic modulus of soft materials with nanosacle resolution. We also discuss several advanced techniques for more elaborate measurements of viscoelastic properties of soft materials and experiments on single cells.
Shintaro Sato 2015 Jpn. J. Appl. Phys. 54 040102
Graphene is a two-dimensional material with a one-atom-thick layer of carbon. Since the first report of the excellent electrical properties of graphene in 2004, its unique physical properties have been attracting attention and research on the application of graphene to electronic and photonic devices has been intensively carried out. In this review, recent research trends in the application of graphene to electronic devices, particularly transistors and interconnects, and graphene formation techniques are examined. In addition, the technical issues to be addressed for its application to electronic devices and the prospects for future graphene devices are discussed.
Ibraheem Almansouri et al 2015 Jpn. J. Appl. Phys. 54 08KD04
Theoretical calculation based on detailed balance and incorporating different realistic optical and electrical losses predicts conversion efficiency beyond 22% for single-junction perovskite devices. In dual-junction perovskite/silicon devices, theoretical conversion efficiency around 40% is been determined. However, dramatic drop in the conversion efficiency is shown to be due to the glass reflection and FTO parasitic absorption losses. Additionally, practical conversion efficiency limits of dual-junction two-terminal perovskite/silicon tandem solar cell of 30% are achievable as reported in this work using state-of-the-art demonstrated devices. Additionally, various crystalline silicon (industry and laboratory demonstrated) technologies are used as the bottom cell for the current matched tandem cell stacks with higher relative improvements when using commercial c-Si solar cells. Moreover, the effect of eliminating the parasitic resistances and enhancing the external radiative efficiency (ERE) in the perovskite junction on tandem performance are also investigated enhancing the stack efficiencies.
Tomoya Koshi and Eiji Iwase 2015 Jpn. J. Appl. Phys. 54 06FP03
We propose a self-healing metal wire using electric field trapping of gold nanoparticles by a dielectrophoresis force. A cracked gold wire can retrieve its conductivity through the self-healing function. In this paper, we examine the healing voltage causing the electric field trapping and determine the healing time, which is relevant to future device applications. First, the forces acting on a nanoparticle are analyzed and a theoretical healing voltage curve is calculated. Then, gold wires with 200- to 1,600-nm-wide cracks are fabricated on glass substrate and the self-healing function is verified through healing experiments. As a result, gold wires with cracks of up to 1,200 nm in width are successfully healed by applying less than ∼2.5 V (on average), and the experimental results correspond almost exactly with the calculated healing voltage curve. The average healing times are 10 to 285 s for 200- to 1,200-nm-wide cracks. Through scanning electron microscope analysis after the healing experiments, we confirm that the cracks are healed by assembled nanoparticles.
Kouhei Yamamoto et al 2015 Jpn. J. Appl. Phys. 54 08KF02
Spin-coated perovskite solar cells from sol–gels result in high processing costs because of the need for high temperatures. Here, we report a low-temperature spin-coating route to fabricate planar heterojunction perovskite solar cells using chemical bath deposition of compact-TiO x layers. Comparison of the solar cell properties of compact-TiO x and compact-TiO 2 layers show that the power conversion efficiency of the planar heterojunction perovskite solar cell fabricated by the low-temperature, compact-TiO x route is comparable to that of conventional TiO 2. The chemical bath deposition method requires heating to 150 °C only to form amorphous compact-TiO x films compared with the 450 °C required for crystalline anatase compact-TiO 2 films.
Shizuo Fujita 2015 Jpn. J. Appl. Phys. 54 030101
Wide-bandgap semiconductors are expected to be applied to solid-state lighting and power devices, supporting a future energy-saving society. While GaN-based white LEDs have rapidly become widespread in the lighting industry, SiC- and GaN-based power devices have not yet achieved their popular use, like GaN-based white LEDs for lighting, despite having reached the practical phase. What are the issues to be addressed for such power devices? In addition, other wide-bandgap semiconductors such as diamond and oxides are attracting focusing interest due to their promising functions especially for power-device applications. There, however, should be many unknown phenomena and problems in their defect, surface, and interface properties, which must be addressed to fully exploit their functions. In this review, issues of wide-bandgap semiconductors to be addressed in their basic properties are examined toward their “full bloom”.
Chao Zhang et al 2015 Jpn. J. Appl. Phys. 54 08LA01
We provide an overview of the development of a merged system of low-temperature ultrahigh-vacuum scanning tunneling microscope (STM) with photon collection and detection units for optical imaging at the nanoscale. Focusing on our own work over the past ten years, the paper starts from a brief introduction of the STM induced luminescence (STML) technique and the challenge for nanoscale optical imaging, and then describes the design and instrumentation on the photon collection and detection system. The powerful potentials of the technique are illustrated using several selected examples from STML to tip enhanced Raman scattering that are mainly related to photon mapping. Such photon maps could reveal not only the local electromagnetic properties and the nature of optical transitions in the junction, but also exhibit spatial imaging resolution down to sub-molecular and sub-nanometer scale. The paper is concluded with a brief overlook on the future development of the STML technique.
Chihaya Adachi 2014 Jpn. J. Appl. Phys. 53 060101
Currently, organic light-emitting diodes (OLEDs) have reached the stage of commercialization, and there are intense efforts to use them in various applications from small- and medium-sized mobile devices to illumination equipment and large TV screens. In particular, phosphorescent materials have become core OLED materials as alternatives to the conventionally used fluorescent materials because devices made with phosphorescent materials exhibit excellent light-emitting performance. However, phosphorescent materials have several problems, such as their structure being limited to organic metal compounds containing rare metals, for example, Ir, Pt, and Os, and difficulty in realizing stable blue light emission, so the development of new materials is necessary. In this article, I will review next-generation OLEDs using a new light-emitting mechanism called thermally activated delayed fluorescence (TADF). Highly efficient TADF, which was difficult to realize with conventional technologies, has been achieved by optimizing molecular structures. This has led to the realization of ultimate next-generation OLEDs that are made of common organic compounds and can convert electricity to light at an internal quantum efficiency of nearly 100%.
Kazuhito Hashimoto et al 2005 Jpn. J. Appl. Phys. 44 8269
Photocatalysis has recently become a common word and various products using photocatalytic functions have been commercialized. Among many candidates for photocatalysts, TiO 2 is almost the only material suitable for industrial use at present and also probably in the future. This is because TiO 2 has the most efficient photoactivity, the highest stability and the lowest cost. More significantly, it has been used as a white pigment from ancient times, and thus, its safety to humans and the environment is guaranteed by history. There are two types of photochemical reaction proceeding on a TiO 2 surface when irradiated with ultraviolet light. One includes the photo-induced redox reactions of adsorbed substances, and the other is the photo-induced hydrophilic conversion of TiO 2 itself. The former type has been known since the early part of the 20th century, but the latter was found only at the end of the century. The combination of these two functions has opened up various novel applications of TiO 2, particularly in the field of building materials. Here, we review the progress of the scientific research on TiO 2 photocatalysis as well as its industrial applications, and describe future prospects of this field mainly based on the present authors' work.
Hiroshi Amano et al 1989 Jpn. J. Appl. Phys. 28 L2112
Distinct p-type conduction is realized with Mg-doped GaN by the low-energy electron-beam irradiation (LEEBI) treatment, and the properties of the GaN p-n junction LED are reported for the first time. It was found that the LEEBI treatment drastically lowers the resistivity and remarkably enhances the PL efficiency of MOVPE-grown Mg-doped GaN. The Hall effect measurement of this Mg-doped GaN treated with LEEBI at room temperature showed that the hole concentration is ∼2·10 16cm -3, the hole mobility is ∼8 cm 2/V·s and the resistivity is ∼35 Ω·cm. The p-n junction LED using Mg-doped GaN treated with LEEBI as the p-type material showed strong near-band-edge emission due to the hole injection from the p-layer to the n-layer at room temperature.
This cloud represents the 50 most popular PACS codes from the latest 250 coded articles for this journal. The larger the code the more times it occurs in those 250 articles. Click on a code to link to the articles in that category.
42.55.Px 43.35.Wa 42.65.Ky 43.38.Fx 42.55.Rz 43.20.Gp 43.38.-p 43.80.Qf 42.15.Eq 43.30.Nb 43.35.Vz 43.60.Rw 42.60.Jf 43.58.Ry 42.65.Re 43.25.-x 43.25.Ts 43.38.Hz 42.60.Lh 43.58.Fm 43.25.Dc 43.30.Cq 43.40.Rj 43.80.Ka 43.35.Ei 43.30.Es 43.25.Vt 42.65.Hw 43.40.Dx 43.64.Bt 07.07.Df 42.81.Uv 43.35.Ty 43.58.-e 43.60.Lq 07.20.Mc 43.50.-x 43.35.Zc 42.65.-k 43.30.-k 43.30.Ma 43.38.Ja 42.70.Mp 43.38.Si 43.35.Hl 42.60.Da 43.20.Hq 43.35.Lq 43.38.Ar 42.60.Fc