Applied Physics Express (APEX) is a letters journal devoted solely to rapid dissemination of up-to-date and concise reports on new findings in applied physics. It is published daily online and monthly for the printed version. The motto of APEX is high scientific quality and prompt publication. APEX is a sister journal of the Japanese Journal of Applied Physics (JJAP) and 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.
2016 Japan Prize honours trailblazer Hideo Hosono
The Japan Society of Applied Physics and IOP Publishing would like to extend their congratulations to Professor Hideo Hosono, who has been awarded the Japan Prize for the "creation of unconventional inorganic materials with novel electronic functions based on nano-structure engineering".
IOP Publishing has introduced a new reprint ordering service accessed via IOPscience, enabling authors and other content users to easily purchase high-quality printed copies of published articles.
The new simple to use service is available for APEX and allows customers to order 25 or more copies of any article with a PDF. All reprints are provided with a cover and in full colour (where colour images were supplied in the article).
The reprints service is accessed directly from the article abstract in IOPscience via the "Buy this article in print" link within the Article Information section. For orders in excess of 250 copies, please contact firstname.lastname@example.org.
JSAP Outstanding Paper Awards
The Japan Society of Applied Physics is pleased to announce the recipients of the latest JSAP Outstanding Paper Awards. These awards honour the authors of papers that are regarded as exceptional achievements in applied physics. The successful papers may be viewed here and are free to read until July 31st, 2016.
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.
In the last 30 days
Akihiro Nakamura et al 2015 Appl. Phys. Express 8 107101
The highest efficiency of 24.4% for the solar-to-hydrogen (STH) energy conversion was obtained in an outdoor field test by combining concentrator photovoltaic (CPV) modules with InGaP/GaAs/Ge three-junction cells and polymer-electrolyte electrochemical (EC) cells. The high efficiency was obtained by using the high-efficiency CPV modules (∼31% under the present operation conditions) and the direct connection between the CPV modules and the EC cells with an almost optimized number of elements in series. The STH efficiency bottleneck was clarified to be the efficiency of the CPV modules, the over-potential of the EC cells, and matching of the operation point to the maximal-power point of the CPV modules.
Sho Okubo et al 2015 Appl. Phys. Express 8 122701
We present an all-optically stabilized, erbium-doped mode-locked fiber laser with an optically pumped ytterbium-doped fiber. The mode-locked fiber laser has two frequency-control actuators that are pump laser powers for erbium-doped and ytterbium-doped fibers. We investigate the frequency-control characteristics of the mode-locked laser and find that the fixed points for the two actuators are sufficiently apart from each other, realizing the simultaneous phase locking of the repetition and carrier envelope offset frequencies. We describe a long-term frequency measurement of an acetylene-stabilized laser at 1542 nm using an all-optically stabilized frequency comb.
Tsukasa Katayama et al 2016 Appl. Phys. Express 9 025801
We investigated the electronic structure of perovskite SrFeO 3− x F x (0.6 ≤ x ≤ 1) films by optical absorption, photoemission, and X-ray absorption spectroscopies, as well as density functional theory (DFT)-based calculations. The optical bandgap expanded with x, yielding a wider direct bandgap for the SrFeO 2F film than for the LaFeO 3 film. The DFT calculations suggested that the majority of FeO 4F 2 octahedra in the SrFeO 2F film had cis configurations and that the enlarged bandgap mainly originated from bond bending in the O–Fe–O chains. We experimentally observed the valence and conduction bands of the SrFeO 2F film, and found them to be qualitatively consistent with the results of DFT-based calculations.
Kazunori Koga et al 2016 Appl. Phys. Express 9 016201
We have studied the effects of air nonthermal plasma irradiation of seeds of Arabidopsis thaliana (L.) on their growth from the beginning of cultivation to their harvest. Three minute plasma irradiation of dry seeds resulted in growth acceleration in all the growth stages. Compared with the control, the plasma irradiation led to an 11% shorter harvest period, a 56% increase in total seed weight, a 12% increase in each seed weight, and a 39% increase in seed number.
Takeru Maekawa et al 2016 Appl. Phys. Express 9 024101
A large increase in oscillation frequency was achieved in resonant-tunneling-diode (RTD) terahertz oscillators by reducing the conduction loss. An n +-InGaAs layer under the air-bridge electrode connected to the RTD was observed to cause a large conduction loss for high-frequency current due to the skin effect. By introducing a new fabrication process removing the InGaAs layer, we obtained 1.92-THz oscillation, which extended the highest frequency of room-temperature electronic single oscillators. Theoretical calculations reasonably agreed with the experiment, and an oscillation above 2 THz is further expected with an improved structure of the slot antenna used as a resonator and radiator.
Yoichi Shiota et al 2016 Appl. Phys. Express 9 013001
We investigated the write error rate (WER) for voltage-driven dynamic switching in magnetic tunnel junctions with perpendicular magnetization. We observed a clear oscillatory behavior of the switching probability with respect to the duration of pulse voltage, which reveals the precessional motion of magnetization during voltage application. We experimentally demonstrated WER as low as 4 × 10 −3 at the pulse duration corresponding to a half precession period (∼1 ns). The comparison between the results of the experiment and simulation based on a macrospin model shows a possibility of ultralow WER (<10 −15) under optimum conditions. This study provides a guideline for developing practical voltage-driven spintronic devices.
Masaya Oda et al 2016 Appl. Phys. Express 9 021101
Thin-film corundum-structured gallium oxide (α-Ga 2O 3) Schottky barrier diodes (SBDs) were fabricated by growing α-Ga 2O 3 layers on sapphire substrates by the safe, low-cost, and energy-saving MIST EPITAXY ® technique, followed by lifting off the α-Ga 2O 3 layers from the substrates. The SBDs exhibited on-resistance and breakdown voltage of 0.1 mΩ·cm 2 and 531 V (SBD1) or 0.4 mΩ·cm 2 and 855 V (SBD2), respectively. These results will encourage the future evolution of low-cost and high-performance SBDs with α-Ga 2O 3.
Daisuke Hayashi et al 2016 Appl. Phys. Express 9 025102
The Seebeck coefficient S and the electrical resistivity ρ of single-wall carbon nanotube (SWCNT) films were investigated as a function of the SWCNT diameter and carrier concentration. The S and ρ significantly changed in humid environments through p-type carrier doping. Experiments, combined with theoretical simulations based on the non-equilibrium Green’s function theory, indicated that the power factor P can be increased threefold by the enrichment of semiconducting SWCNTs, but the nanotube diameter has little effect. The improvement of the film resistivity strongly enhances the film thermoelectric performance, manifested as increasing the value of P above 1200 µW/(m·K 2).
Yoshiya Sakai et al 2015 Appl. Phys. Express 8 096601
Molecular orientation in organic light-emitting diodes (OLEDs) is now regarded as an important factor that affects device efficiency. However, methods to quantitatively estimate the degree of molecular orientation in OLEDs are currently limited, and they require constructing a model of an optical structure. Here, we propose a simple model-free method to estimate the orientation order parameters ( S) of molecules in amorphous OLED films from their absorption spectra using the randomization of molecular orientation induced by heating. This method is used to quantitatively estimate the S values of vacuum-deposited and spin-coated films and clearly demonstrate the random orientation in the latter.
Takumi Miyakawa et al 2016 Appl. Phys. Express 9 023103
Efficient gate control of spin-valve signals and Hanle signals was achieved in a GaAs channel with a p–i–n back-gate structure. Experiments showed that the amplitude of the spin-valve signal (Δ V NL) under constant-injection-current conditions increased for a cross nonlocal geometry when the channel was depleted by the gate voltage ( V G). In contrast, the V G dependence of Δ V NL for a nonlocal geometry was complicated. The gate modulation efficiency of spin signals was approximately 50 times that with a graphene or Si channel.
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 42.70.Df 42.65.Ky 42.60.Pk 07.20.Pe 07.57.Hm 06.30.Ft 42.60.Lh 42.79.Nv 42.65.Pc 02.70.Bf 42.79.Sz 41.75.Fr 42.70.Hj 42.55.Lt 42.65.Jx 03.67.Lx 07.20.Dt 05.40.Ca 42.81.Dp 37.10.De 42.79.Bh 42.55.Sa 42.30.Wb 42.25.Bs 33.50.Dq 05.10.Ln 42.81.Ht 42.60.Fc 42.79.Pw 42.55.Rz 42.72.Bj 42.55.Wd 42.70.Qs 42.60.Jf 07.57.Kp 42.70.Jk 42.79.Dj 37.30.+i 42.25.Ja 42.81.Pa 07.07.Df 42.55.Xi 07.60.Ly 42.79.Gn 42.60.Da 42.79.Ci 42.79.Wc 42.40.Lx 07.57.-c