Journal of the Korean Physical Society最新文献

{"title":"Erratum: Existence of symmetry-broken excited states in single and ensemble quantum ring structures","authors":"Hyoseong Jang, Seung Kwon Jeon, Seungmin Jeong, Heedae Kim","doi":"10.1007/s40042-024-01247-9","DOIUrl":"10.1007/s40042-024-01247-9","url":null,"abstract":"","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"85 12","pages":"1062 - 1062"},"PeriodicalIF":0.8,"publicationDate":"2024-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142826252","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correlation between the gain factor of a reflective polarizer and the optical structure of quantum dot-based backlights for LCD applications","authors":"Sang-min Lee,&nbsp;Hyeon-Ho Choo,&nbsp;Jun-Hyeok Jang,&nbsp;Min-Jun Kwak,&nbsp;Eunki Baek,&nbsp;Sohee Kim,&nbsp;Jae-Hyeon Ko","doi":"10.1007/s40042-024-01164-x","DOIUrl":"10.1007/s40042-024-01164-x","url":null,"abstract":"<div><p>The optical gain factor of a reflective polarizer in a quantum dot (QD)-based edge-lit backlight was investigated for the first time with various optical film combinations. The QD film, containing red and green quantum dots, was excited by 20 blue LEDs arranged near the light guide plate (LGP). The multilayer-type reflective polarizer significantly altered the color properties of the QD backlight by enhancing QD film excitation through its reflective properties. The gain factor was nearly two when only a single QD film was placed over the LGP without additional optical films, indicating minimal optical loss. However, the gain factor decreased significantly with the addition of prism sheets, likely due to the formation of a strong optical cavity between the bottom reflector and the prism grooves. This suggests that the optical configuration of QD-based backlights should be carefully optimized to account for color changes due to the reflective polarizer and to avoid strong optical cavity effects caused by prism sheets.</p></div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"85 11","pages":"915 - 922"},"PeriodicalIF":0.8,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142761865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Systematic investigation of nanofluids: impact of nanoparticle charge and temperature on thermophysical properties","authors":"Taeil Yi","doi":"10.1007/s40042-024-01225-1","DOIUrl":"10.1007/s40042-024-01225-1","url":null,"abstract":"<div><p>This study systematically investigates the effects of nanoparticle (NP) charge and temperature on the thermophysical properties of nanofluids using molecular dynamics simulations. The interaction between charged nanoparticles and solvent particles significantly influences both viscosity and thermal conductivity. The nanoparticles are modeled with varying charges, and their impact on fluid behavior is analyzed in terms of radial distribution functions, viscosity, and thermal conductivity, computed using the Green-Kubo formalism. The findings reveal that increased NP charge leads to reduced aggregation, enhancing dispersion and lowering viscosity, while thermal conductivity exhibits complex behavior, decreasing with NP charge at moderate temperatures but increasing in the supercritical region. Temperature also plays a critical role, with nanofluids demonstrating typical shear-thinning behavior and a distinct phase-dependent response in thermal conductivity. These results provide valuable insights into optimizing nanofluid properties for applications such as coolant systems and lubricants, where both efficient heat transfer and low energy dissipation are crucial. The systematic analysis of charge and temperature effects contributes to a better understanding of the underlying mechanisms governing nanofluid behavior.</p></div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"85 12","pages":"1041 - 1049"},"PeriodicalIF":0.8,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142826237","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Insights and guidelines on the Cauchy horizon theorems","authors":"Xiao Yan Chew,&nbsp;Dong-han Yeom","doi":"10.1007/s40042-024-01210-8","DOIUrl":"10.1007/s40042-024-01210-8","url":null,"abstract":"<div><p>Recently, there has been progress to resolve the issue regarding the non-existence of the Cauchy horizon inside the static, charged, and spherically symmetric black holes. However, when we generically extend the black holes’ spacetime, they are not just static but can be dynamical, thus the interior of black holes does not remain the same as the static case when we take into account the dynamical evolution of black holes. Hence, the properties of the Cauchy horizon could behave differently in the dynamical case. Then, our aim in this paper is to provide a few constructive insights and guidelines regarding this issue by revisiting a few examples of the gravitational collapse of spherically symmetric charged black holes using the double-null formalism. Our numerical results demonstrate that the inside of the outer horizon is no longer static even in late time, and the inner apparent horizon exists but is not regular. The inner apparent horizon can be distinguished clearly from the Cauchy horizon. The spherical symmetric property of black holes allows the inner horizon to be defined in two directions, i.e., the differentiation of the areal radius vanishes along either the out-going or the in-going null direction. Moreover, the Cauchy horizon can be generated from a singularity. Still, the notion of the singularity can be subtle where it can have a vanishing or non-vanishing areal radius; the corresponding curvature quantities could be finite or diverge, although the curvatures can be greater than the Planck scale. Finally, we show some examples that the “hair” which is associated with the matter field on the inner horizon is not important to determine the existence of the Cauchy horizon; rather, the hair on the outer horizon might play an important role on the Cauchy horizon. Therefore, the dynamic properties of the interior of charged black holes could shed light for us to understand deeply about the Cauchy horizon for the extensions of no-Cauchy-horizon theorems.</p></div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"85 12","pages":"1050 - 1061"},"PeriodicalIF":0.8,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142826404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simultaneous analysis of rotational and vibrational spectra in even–even deformed nuclei: a study on (^{168})Er","authors":"Su Youn Lee","doi":"10.1007/s40042-024-01219-z","DOIUrl":"10.1007/s40042-024-01219-z","url":null,"abstract":"<div><p>Theoretical studies of nuclear structure play a crucial role in understanding the collective properties of nuclei. In this study, we investigated the collective properties of even–even deformed nuclei with simultaneous nuclear rotational and vibrational spectra. From the nuclear Hamiltonian, the low-lying energy levels, and interband and intraband <i>E</i>2 transition probabilities were derived analytically. The Hamiltonian proposed in this study is based on the geometrical model proposed by Bohr and Mottelson representing a typical collective model, and the algebraic model proposed by Arima and Iachello. The energy levels and <i>E</i>2 transition ratios of <span>(^{168})</span>Er were calculated and compared with the experimental data. This theoretical approach effectively described the structure of the deformed nucleus <span>(^{168})</span>Er.</p></div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"85 12","pages":"977 - 983"},"PeriodicalIF":0.8,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142826085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Transferred single-layer graphene on pre-patterned metal electrode: comparison of thermoelectric and electric properties","authors":"Hye-Mi So,&nbsp;Hyun-June Jung,&nbsp;Sanghee Cho","doi":"10.1007/s40042-024-01218-0","DOIUrl":"10.1007/s40042-024-01218-0","url":null,"abstract":"<div><p>The graphene synthesized by the chemical vapor deposition (CVD) method on Cu foil was transferred onto the SiO₂ substrate with a pre-patterned electrode, and the electrical and thermoelectric properties were measured. Raman spectral analysis and thermoelectric coefficient measurement confirmed that the transferred graphene is mainly composed of single-layer and has <i>p</i>-type properties. The thermoelectric characteristics of the transferred graphene as well as the thermoelectric voltage image mapping in the locally torn, folded or bubbled region of graphene by the scanning probe method using the thermoelectric phenomenon were confirmed on a micro-scale.</p></div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"85 12","pages":"1022 - 1031"},"PeriodicalIF":0.8,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142826086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Making public reputation out of private assessments","authors":"Youngsuk Mun,&nbsp;Quang Anh Le,&nbsp;Seung Ki Baek","doi":"10.1007/s40042-024-01192-7","DOIUrl":"10.1007/s40042-024-01192-7","url":null,"abstract":"<div><p>Reputation is not just a simple opinion that an individual has about another, but a social construct that emerges through communication. Despite the huge importance in coordinating human behavior, such a communicative aspect has remained relatively unexplored in the field of indirect reciprocity. In this work, we bridge the gap between private assessment and public reputation. We begin by clarifying what we mean by reputation and argue that the formation of reputation can be modeled by a bi-stochastic matrix, provided that both assessment and behavior are regarded as continuous variables. By choosing bi-stochastic matrices that represent averaging processes, we show that only four norms among the leading eight, which judge a good person’s cooperation toward a bad one as good, will keep cooperation asymptotically or neutrally stable against assessment error in a homogeneous society where every member has adopted the same norm. However, when one of those four norms is used by the resident population, the opinion averaging process allows neutral invasion of mutant norms with small differences in the assessment rule. Our approach provides a theoretical framework for describing the formation of reputation in mathematical terms.</p></div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"85 12","pages":"969 - 976"},"PeriodicalIF":0.8,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142826403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Self-powered visible-blind ultraviolet photodetectors based on SnO2 nanowire cotton synthesized using thermal chemical vapor deposition","authors":"Mijin Park,&nbsp;Hyon Chol Kang","doi":"10.1007/s40042-024-01214-4","DOIUrl":"10.1007/s40042-024-01214-4","url":null,"abstract":"<div><p>We report a simple method for fabricating a SnO₂ nanowire (NW) cotton-based ultraviolet (UV) photodetector. SnO₂ NW cotton was synthesized by thermal chemical vapor deposition with SnO powder. Ag paste was coated onto the surface of the SnO₂ NW cotton to serve as the electrode. The performance of the photodetector was evaluated upon UV light exposure at a wavelength of 254 nm, with a photo-to-dark-current ratio of 7.9 × 10⁵, photoresponsivity of 1.141 × 10³ A/W, and specific detectivity of 9.0 × 10¹⁵ Jones. The spectral photoresponsivity was also determined in the 200–600 nm wavelength range. The results showed a maximum responsivity at 270 nm and a cutoff edge wavelength of 360 nm, exhibiting the characteristics of a visible-blind UV photodetector. In addition, self-powered capability with a photocurrent of 2.3 nA was demonstrated at a nominal zero bias.</p></div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"85 12","pages":"1015 - 1021"},"PeriodicalIF":0.8,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142826335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Existence of symmetry-broken excited states in single and ensemble quantum ring structures","authors":"Hyoseong Jang,&nbsp;Seung Kwon Jeon,&nbsp;Seungmin Jeong,&nbsp;Heedae Kim","doi":"10.1007/s40042-024-01203-7","DOIUrl":"10.1007/s40042-024-01203-7","url":null,"abstract":"<div><p>Power-dependent time-integrated/time-resolved photoluminescence (PL) measurements of the quantum ring (QR) structures were performed under 4 K. As excitation power is increased, the exciton and biexciton states were confirmed by linearly and superlinearly increasing power factors, respectively. Notably, the power-dependent blue shift showed fine structure splitting owing to the diverse sizes of the excited states. These different excited states could be distinguished by measuring the power-dependent decay times. Asymmetric electron–hole exchange interactions, attributed to the different sizes of energy states and different oscillator strengths between the ground and excited exciton states, were analyzed using time-resolved PL techniques. The various excited states were resolved based on their exponential decay rates.</p></div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"85 12","pages":"1010 - 1014"},"PeriodicalIF":0.8,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142826334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Defect-rich sunlight-responsive SnO2 photocatalyst for methyl orange dye degradation: a step towards wastewater treatment","authors":"Rituraj Mahanta,&nbsp;Pawan Chetri,&nbsp;Nikhil Parasar,&nbsp;Dimishree Neog,&nbsp;Bidhan Mohanta","doi":"10.1007/s40042-024-01211-7","DOIUrl":"10.1007/s40042-024-01211-7","url":null,"abstract":"<div><p>This study examines the potential of defect-engineered pure SnO₂ nanoparticles as efficient photocatalysts for wastewater treatment under sunlight irradiation. Two distinct SnO₂ nanosystems are synthesized through a facile and cost-effective sol–gel approach. Defects are deliberately introduced into one of the samples by altering the annealing process. After the formation of SnO₂ gel, this sample undergoes rapid cooling between two consecutive annealing stages of 2 h and 4 h at 100 ℃ under vacuum conditions respectively. In contrast, the other sample is subjected to conventional annealing in a hot air environment at 400 ℃ for 24 h. The structural and optical properties of these samples are meticulously characterized using X-ray diffraction, UV–visible spectroscopy, TEM, FTIR, BET and EPR respectively. Subsequently, the photocatalytic performance of both SnO₂ nanoparticle samples is evaluated by degrading a methyl orange solution, which serves as a model contaminant for textile industry wastewater under sunlight exposure. The defect-engineered SnO₂ sample demonstrates a remarkable improvement in photocatalytic efficiency, degrading 82.51% of methyl orange with a rate constant of 0.02886 min⁻¹ under 60 min of sunlight irradiation. In comparison, the standard SnO₂ sample degrades only 29.71% of methyl orange, with a significantly lower rate constant of 0.00575 min⁻¹ under the same irradiation conditions. This improvement is attributed to the increased number of defect sites (oxygen vacancy), surface area (59.877 m²/gm) and narrow optical bandgap (2.85 eV), which enhance light absorption and generate more active excitons, thus accelerating the degradation process. The novelty of this research lies in the successful enhancement of photocatalytic performance without the need for doping or composite formation, making it a cost-effective and scalable approach for wastewater treatment applications.</p></div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"85 12","pages":"996 - 1009"},"PeriodicalIF":0.8,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40042-024-01211-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142826333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}