Search

In this study, we propose technologies for the device structure, gate fabrication process, and back-bias-assisted operation of Si spin qubits to realize the high robustness of the two-qubit SWAP gate operation against process variations. We performed quantum device simulations for MOS-type two-qubit devices and verified the benefits of these technologies on the SWAP gate fidelity. We clarified that these technologies significantly improve the robustness of the SWAP gate operation against process variations and achieve a 6σ-yield SWAP gate operation with 99% fidelity, assuming device size fluctuation of the International Roadmap for Devices and Systems (IRDS) target for 2022. The proposed technologies provide a solution for completing a universal quantum gate set for realizing universal quantum computers with silicon.

In ships’ cargo spaces carrying vehicles, so called “vehicle spaces”, fire has sometimes taken place and safety measures against such fire is under discussion at the International Maritime Organization (IMO). Early detection of fire is one of the essential elements of such safety measures. Location of fire detectors affects swiftness of detection of fire, and in onshore buildings, fire detectors are generally installed directly on ceilings because there are no obstacles under ceilings and smoke spreads along the ceilings. On the other hand, structures below ceilings, i.e., decks, of vehicle spaces are quite different from those of onshore buildings due to strength members below a deck, such as stiffeners and web beams. The appropriate positions of smoke detectors in a vehicle space, including vertical positions of detectors from a ceiling, has not been well-understood, while the maximum coverage of a detector is determined by an international regulation. In this study, the effect of structures below the ceilings of vehicle spaces on detection of fire has been investigated and the appropriate positions of smoke detectors including vertical positions have been considered, in particular, for smouldering fire sources. For this purpose, a one-sixth scaled deck model was prepared to simulate a part of a vehicle space and fire experiments were conducted using a small-scaled fire source. The effect of the structure on a smoke flow beneath the ceiling was experimentally investigated under the condition that the flow had a weak driving force in a smouldering fire or an early stage of fire. In the experiment, the flow was visualized using a laser and the smoke density expressed with the extinction coefficient was also measured. In addition, a small flaming fire source was used during the experiment, to further investigate a possibility of detection in an early stage of fire. The vertical profiles of smoke density were measured using the laser transmissometer. Furthermore, a smoke flow was visualized using continuous wave laser. As the results, it is concluded that it is appropriate to install smoke detectors at the lower end of the longitudinal stiffener, instead of installing on the ceilings in vehicle spaces.

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.--Full list of authors: Acciari, V. A.; Aniello, T.; Ansoldi, S.; Antonelli, L. A.; Arbet Engels, A.; Artero, M.; Asano, K.; Baack, D.; Babić, A.; Baquero, A.; Barres de Almeida, U.; Barrio, J. A.; Batković, I.; Becerra González, J.; Bednarek, W.; Bernardini, E.; Bernardos, M.; Berti, A.; Besenrieder, J.; Bhattacharyya, W.; Bigongiari, C.; Biland, A.; Blanch, O.; Bökenkamp, H.; Bonnoli, G.; Bošnjak, Ž.; Busetto, G.; Carosi, R.; Ceribella, G.; Cerruti, M.; Chai, Y.; Chilingarian, A.; Cikota, S.; Colombo, E.; Contreras, J. L.; Cortina, J.; Covino, S.; D'Amico, G.; D'Elia, V.; Vela, P. Da; Dazzi, F.; De Angelis, A.; De Lotto, B.; Del Popolo, A.; Delfino, M.; Delgado, J.; Mendez, C. Delgado; Depaoli, D.; Di Pierro, F.; Di Venere, L.; Do Souto Espiñeira, E.; Dominis Prester, D.; Donini, A.; Dorner, D.; Doro, M.; Elsaesser, D.; Fallah Ramazani, V.; Fariña, L.; Fattorini, A.; Font, L.; Fruck, C.; Fukami, S.; Fukazawa, Y.; García López, R. J.; Garczarczyk, M.; Gasparyan, S.; Gaug, M.; Giglietto, N.; Giordano, F.; Gliwny, P.; Godinović, N.; Green, J. G.; Green, D.; Hadasch, D.; Hahn, A.; Hassan, T.; Heckmann, L.; Herrera, J.; Hoang, J.; Hrupec, D.; Hütten, M.; Inada, T.; Iotov, R.; Ishio, K.; Iwamura, Y.; Jiménez Martínez, I.; Jormanainen, J.; Jouvin, L.; Kerszberg, D.; Kobayashi, Y.; Kubo, H.; Kushida, J.; Lamastra, A.; Lelas, D.; Leone, F.; Lindfors, E.; Linhoff, L.; Lombardi, S.; Longo, F.; López-Coto, R.; López-Moya, M.; López-Oramas, A.; Loporchio, S.; Machado de Oliveira Fraga, B.; Maggio, C.; Majumdar, P.; Makariev, M.; Mallamaci, M.; Maneva, G.; Manganaro, M.; Mannheim, K.; Mariotti, M.; Martínez, M.; Mas Aguilar, A.; Mazin, D.; Menchiari, S.; Mender, S.; Mićanović, S.; Miceli, D.; Miener, T.; Miranda, J. M.; Mirzoyan, R.; Molina, E.; Moralejo, A.; Morcuende, D.; Moreno, V.; Moretti, E.; Nakamori, T.; Nava, L.; Neustroev, V.; Nievas Rosillo, M.; Nigro, C.; Nilsson, K.; Nishijima, K.; Noda, K.; Nozaki, S.; Ohtani, Y.; Oka, T.; Otero-Santos, J.; Paiano, S.; Palatiello, M.; Paneque, D.; Paoletti, R.; Paredes, J. M.; Pavletić, L.; Peñil, P.; Persic, M.; Pihet, M.; Prada Moroni, P. G.; Prandini, E.; Priyadarshi, C.; Puljak, I.; Rhode, W.; Ribó, M.; Rico, J.; Righi, C.; Rugliancich, A.; Sahakyan, N.; Saito, T.; Sakurai, S.; Satalecka, K.; Saturni, F. G.; Schleicher, B.; Schmidt, K.; Schmuckermaier, F.; Schweizer, T.; Sitarek, J.; Šnidarić, I.; Sobczynska, D.; Spolon, A.; Stamerra, A.; Strišković, J.; Strom, D.; Strzys, M.; Suda, Y.; Surić, T.; Takahashi, M.; Takeishi, R.; Tavecchio, F.; Temnikov, P.; Terzić, T.; Teshima, M.; Tosti, L.; Truzzi, S.; Tutone, A.; Ubach, S.; van Scherpenberg, J.; Vanzo, G.; Vazquez Acosta, M.; Ventura, S.; Verguilov, V.; Viale, I.; Vigorito, C. F.; Vitale, V.; Vovk, I.; Will, M.; Wunderlich, C.; Yamamoto, T.; Zarić, D.; Hodges, M.; Hovatta, T.; Kiehlmann, S.; Liodakis, I.; Max-Moerbeck, W.; Pearson, T. J.; Readhead, A. C. S.; Reeves, R. A.; Lähteenmäki, A.; Tornikoski, M.; Tammi, J.; D'Ammando, F.; Marchini, A.; MAGIC Collaboration; OVRO Collaboration; Metsahovi Collaboration., The blazar TXS 0506+056 got into the spotlight of the astrophysical community in 2017 September, when a high-energy neutrino detected by IceCube (IceCube-170922A) was associated at the 3σ level with a γ-ray flare from this source. This multi-messenger photon-neutrino association remains, as per today, the most significant association ever observed. TXS 0506+056 was a poorly studied object before the IceCube-170922A event. To better characterize its broadband emission, we organized a multiwavelength campaign lasting 16 months (2017 November to 2019 February), covering the radio band (Metsähovi, OVRO), the optical/UV (ASAS-SN, KVA, REM, Swift/UVOT), the X-rays (Swift/XRT, NuSTAR), the high-energy γ rays (Fermi/LAT), and the very high-energy (VHE) γ rays (MAGIC). In γ rays, the behavior of the source was significantly different from the behavior in 2017: MAGIC observations show the presence of flaring activity during 2018 December, while the source only shows an excess at the 4σ level during the rest of the campaign (74 hr of accumulated exposure); Fermi/LAT observations show several short (on a timescale of days to a week) flares, different from the long-term brightening of 2017. No significant flares are detected at lower energies. The radio light curve shows an increasing flux trend that is not seen in other wavelengths. We model the multiwavelength spectral energy distributions in a lepto-hadronic scenario, in which the hadronic emission emerges as Bethe-Heitler and pion-decay cascade in the X-rays and VHE γ rays. According to the model presented here, the 2018 December γ-ray flare was connected to a neutrino emission that was too brief and not bright enough to be detected by current neutrino instruments. © 2022. The Author(s). Published by the American Astronomical Society., The financial support of the German BMBF, MPG, and HGF; the Italian INFN and INAF; the Swiss National Fund SNF; the ERDF under the Spanish Ministerio de Ciencia e Innovación (MICINN) (PID2019-104114RB-C31, PID2019-104114RB-C32, PID2019-104114RB-C33, PID2019-105510GB-C31,PID2019-107847RB-C41, PID2019-107847RB-C42, PID2019-107847RB-C44, PID2019-107988GB-C22); the Indian Department of Atomic Energy; the Japanese ICRR, the University of Tokyo, JSPS, and MEXT; the Bulgarian Ministry of Education and Science, National RI Roadmap Project DO1-400/18.12.2020 and the Academy of Finland grant nr. 320045 is gratefully acknowledged. This work was also supported by the Spanish Centro de Excelencia "Severo Ochoa" (SEV-2016-0588, SEV-2017-0709, CEX2019-000920-S), the Unidad de Excelencia "María de Maeztu" (CEX2019-000918-M, MDM-2015-0509-18-2) and by the CERCA program of the Generalitat de Catalunya; by the Croatian Science Foundation (HrZZ) Project IP-2016-06-9782 and the University of Rijeka Project 13.12.1.3.02; by the DFG Collaborative Research Centers SFB823/C4 and SFB876/C3; the Polish National Research Centre grant UMO-2016/22/M/ST9/00382; and by the Brazilian MCTIC, CNPq and FAPERJ. E.P. acknowledges funding from the Italian Ministry of Education, University and Research (MIUR) through the "Dipartimenti di eccellenza" project Science of the universe. M.C. has received financial support through the Postdoctoral Junior Leader Fellowship Programme from la Caixa Banking Foundation, grant No. LCF/BQ/LI18/11630012. This research has made use of data from the OVRO 40 m monitoring program, which was supported in part by NASA grants NNX08AW31G, NNX11A043G, and NNX14AQ89G, and NSF grants AST-0808050 and AST-1109911, and private funding from Caltech and the MPIfR. This publication makes use of data obtained at Metsähovi Radio Observatory, operated by Aalto University in Finland.

We theoretically analyze the transient dynamics in two-photon absorption (TPA) driven by a rectangular pulse consisting of entangled photons with time delay in terms of verifying the quantum virtual-state spectroscopy (VSS) method. We consider two types of three-level atomic systems: one is the atomic system having an intermediate state between ground and excited states, considered in common TPA, and another is the atomic system having an intermediate state above the excited state, assumed in the original VSS theory. We show that for common TPA configuration VSS does not occur at all, whereas for the original VSS configuration VSS-like signals can be obtained regardless of whether the incident photons are entangled or not, where photon entanglement simply contributes to the enhancement of the signal. In addition, by introducing frequency cutoff to the spectrum of incident photons, we also show that the VSS-like signal disappears even for the original VSS configuration when the intermediate state is completely virtually excited. Thus, the obtained results suggest that both the broad spectrum of incident photons causing the real excitation of intermediate state and energy configuration of intermediate state above the excited state are essential for VSS-like signals and that VSS in itself does not occur in a strict sense at least. The effect of unphysical parameters appearing in the original VSS scheme, recently theoretically predicted, is also discussed.

The sub-threshold swing (SS) of Si n-MOSFETs is experimentally and systematically evaluated in a temperature range of 4–300 K with varying the substrate impurity concentration (N sub) from ~1016 to ~1018 cm−3, to obtain a physical understanding of SS at cryogenic temperatures. It is clarified that the temperature and drain current dependencies of SS in n-MOSFETs are well represented by a model composed of mobile tail states and localized interface states, irrespective of N sub. The densities of these states are found to increase with increasing N sub. A physical origin of band tail states is studied by experimentally examining the impact of substrate bias on these states, which can separate the effects of the N sub and the surface electric field. It has been clarified, as a result, that the band tail states can be explained by the impurity-induced model.

To reduce heatstroke cases, the Japanese government launched ‘Heatstroke Alert’ in 2020. In this initiative, an alert is issued when the daily maximum wet bulb globe temperature (WBGT) is expected to reach or exceed 33 °C. However, heatstroke incidents at a daily maximum of WBGT of 33 °C can vary by regions and by age groups. In this study, we analyzed the heatstroke incidence in all 47 prefectures of Japan at the daily maximum WBGT of 33 °C, considering age groups. In addition, considering variations in heatstroke incidence by prefectures and age groups, alternative ‘Heatstroke Alert’ criteria (AHAC) by each prefecture and age group were examined. We also analyzed the daily maximum WBGT at which heatstroke incidence starts to increase (the WBGT threshold), as this can be an additional metric to ‘Heatstroke Alert’ for the prevention of heatstroke. The results showed that the northern region (higher latitudes) of Japan has more patients with heatstroke per population, at a daily maximum WBGT of 33 °C, than the southern region (lower latitudes), by factors of approximately 3–5, considering each age group. The suggested AHAC among 47 prefectures were 29.8 [27.7–31.4] °C for 7–17 years, 32.4 [30.2–33.9] °C for 18–64 years, and 30.8 [28.5–33.2] °C for ≥ 65 years, respectively. The northern region exhibited a lower WBGT threshold (defined as the value at which heatstroke incidence is 0.1 persons per 105 people) than the southern region by approximately 3.5°C–5°C, considering each age group. The calculated average WBGT threshold among 47 prefectures was 23.2 [20.4–25.3] °C for 7–17 years, 26.3 [24.2–28.1] °C for 18–64 years, and 23.1 [20.2–25.6] °C for ≥ 65 years, respectively. These findings are expected to contribute to the reinforcement of ‘Heatstroke Alert’ and the use of WBGT information in a more preventive manner.

A series resistance extraction method proposed recently, which uses multiple drain current versus gate voltage curves at varied drain voltages, was applied to bulk CMOS devices at low temperatures down to 4 K. A moderate reduction of series resistance compared with 300 K was found. Horizontal field dependence of mobility significantly changed with temperature, which was taken into account during the extraction. Anomalous non-linear series resistance was observed at 4 K only for p-channel FETs, suggesting the need for careful source/drain overlap design for low temperature operations.

More than industrial trash, household liquid waste is a societal concern caused by human activities. Using Pumakkal starters, this research turns domestic liquid waste into organic fertilizer. This research was conducted in several stages. The first was to make household waste liquid fertilizer with pumakkal formula P1 (3 bacterial isolates), P2 (6 bacterial isolates), P3 (9 bacterial isolates), P4 (12 bacterial isolates), P5 (15 bacterial isolates). The second was the test quality of household waste liquid fertilizers. The results showed the levels of NPK have quality standards of 2-6% with grades N (0,337), P (1,755), and K (3,818) at the highest treatment, and the values of N, P, K meet SNI. The C-Organic levels have a quality standard (minimum 10) with the value of 15,706 in the P5 treatment, and thus C-Organic exceeds SNI. The ratio level of C/N has a quality standard (≤25) with a value of 93,191 at the smallest P5 treatment compared to other treatments resulting in the ratio of C/N exceeding SNI. The pH has a quality standard (4-9) with a value of 6,176 on the P5 treatment, so the pH has met the SNI.

Indoor air quality can be maintained by using an air purifier. Increasing the absorption of particulates (PM) in the air purifier can be done by adding photocatalyst ceramics. This study aims to determine the impact of adding photocatalyst ceramics to an air purifier. A simple reactor resembling an air purifier was made, to which a photocatalyst ceramic was added. The PM remaining in the output air is then analyzed based on the rate of photocatalytic degradation. The results showed that the use of photocatalyst ceramics can accelerate the absorption of PM compared to without using it.

Cellular responses to molecularly targeted agents (gefitinib and osimertinib) have been observed in cultured cancer cells using ultra-broadband multiplex coherent anti-Stokes Raman scattering and third harmonic generation microscopy. Lipid droplets (LDs) appeared in the cells 48 h after the exposure of cancer cells to gefitinib. This was also observed in the gefitinib-resistant strain, and the accumulation of LDs was significant. When exposed to osimertinib, LDs were not as pronounced as those with gefitinib. These agents act on cells through different mechanisms.