Current Issue
February 2025
Vol. 70
pISSN 1567-1739eISSN 1567-1739
Light-induced negative differential resistance effect in a resistive switching memory device
pISSN 1567-1739
eISSN 1567-1739
February 2025Feb 01, 2025Current IssueVol. 70
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Article 2025-02-28
Improved thermoelectric properties of the β-Cu2+xSe/CuInSe2 multilayer films by layer interface scattering
Chen Y.; Song G.; Ben Z.; Wu Y.; You J.Curr. Appl. Phys. 2025; 70: 1-10Abstract : The β-Cu2+xSe/CuInSe2 multilayer films with different modulation period were prepared and studied. The results showed that the deposited films possessed obvious layered structure. The room temperature carrier concentration, mobility, electrical conductivity and thermal conductivity decreased, but the Seebeck coefficient and power factor and relative thermoelectric figure of merit increased with reducing modulation period of deposited β-Cu2-xSe/CuInSe2 multilayer films. The linear reduction of carrier concentration and mobility and the decrease in thermal conductivity with modulation period was attributed to the scattering of carriers and phonons by layer interface and grain boundary, respectively. The sample with the smallest modulation period (160 nm) possessed the highest power factor of ∼0.74 at room temperature and ∼1.56 mW m−1 K−2 at 405 °C. The insertion of heterogeneous layer into films is an effective method to increase Seebeck coefficient and decrease thermal conductivity, thus increasing thermoelectric figure of merit of films. © 2024 Korean Physical Society
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Article 2025-02-28
Comparison of ex-situ solid and liquid iodine doping methods at different temperatures to improve electrical properties of polythiophene nanostructure films synthesized by atmospheric pressure plasma process
Suleiman H.O.; Jung E.Y.; Jang H.; Kim J.Y.; Tae H.-S.Curr. Appl. Phys. 2025; 70: 11-20Abstract : Despite advancements in research on conducting polymers, obtaining stable conductivity in thin films remains challenging. Although ex-situ iodine (I2) doping methods have exhibited promise, they often result in unstable conductivity with increasing exposure time. This study aimed to produce polythiophene (PTh) nanostructure films with stable electrical conductivity through optimized ex-situ I2-doping techniques using a newly fabricated atmospheric pressure plasma reactor for PTh deposition. I2 charge carriers in the form of solid and liquid were separately incorporated into the PTh at room temperatures and 60 °C. FE-SEM, EDS, and FT-IR revealed an enhanced molecular structure, the distribution of element and functional chemical composition of the doped PTh nanostructure films, respectively. Compared to solid I2 doping, the liquid-doped PTh exhibited improved electrical conductivity and stable conductivity over a long period. The results also proved promising for reliable applications in electronic devices, making ex-situ liquid I2 doping a good technique. © 2024 Korean Physical Society
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Article 2025-02-28
Impact analysis of various types of simulated multiple scattering matrices on the numerical simulation of high-resolution imaging in scattering media
Lee Y.-R.Curr. Appl. Phys. 2025; 70: 21-26Abstract : Optical techniques are essential in biomedical research, enabling high-resolution, non-invasive imaging of biological tissues. However, imaging depth in optical microscopy is limited by multiple scattering in scattering media, such as biological tissues. Various methods have been developed to overcome this limitation, and numerical simulations have played an important role in developing new imaging techniques. Traditional simulations often use simple random matrices to represent multiple-scattered waves, which overly simplifies their behavior and may impact the accuracy of image quality assessments. In this study, we introduce various types of simulated multiple scattering matrices to better capture the characteristics of scattered waves. We systematically analyze the correlation properties of these matrices and evaluate their impact on high-resolution imaging quality. This work provides a foundation for selecting appropriate matrix types for simulating multiple scattering effects, aiding in the effective testing and validation of new microscopy techniques in scattering media. © 2024 Korean Physical Society
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Article 2025-02-28
Analysis of electron thermal properties in Ar/O2 inductively coupled plasmas: A global model simulation using Langmuir probe data
Seo H.; Lee H.; Kwon J.-W.; Kim G.; Lee I.; Kim G.-H.Curr. Appl. Phys. 2025; 70: 27-40Abstract : This study investigates the electron thermal properties in Argon and Ar/O2 inductively coupled plasmas using global model based on Langmuir probe data. The sensor-data driven global model (GM) is improved to simulate the power coupling efficiency and an electron energy distribution simultaneously. It reveals that the heating characteristic changes the thermal state and radical generation with input power, pressure and gas mixture ratio. The analysis results of probe data from the global model provide information on the plasma thermal characteristics under efficient operating conditions of process plasma. It provides the advantage of offering insights into the causes of variations in the plasma thermal equilibrium state with operating conditions in ICP, which are limited to obtain from the sensor or the general GM. This makes it highly promising as a simulation method for developing process recipes. © 2024 Korean Physical Society
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Article 2025-02-28
Near-field infrared spectroscopy: Advanced research method in thin film analysis
Kim J.; Chae B.; Lee S.Curr. Appl. Phys. 2025; 70: 41-50Abstract : This article introduces several cases of s-SNOM (Scattering-type scanning near-field optical microscopy) based on a SPM (Scanning probe microscopy) for chemical thin film. A highly concentrated near-field infrared performs the chemical analysis of s-SNOM at the sharp apex of the metal-coated atomic microscope tip. This attractive technique, which provides both surface morphology and chemical information of the material simultaneously, various studies have been published, including surface polariton propagation, Moire superlattice, and ballistic valley transport. Further, s-SNOM successfully visualized the formation of lamellar nanostructures of BCP and the latent image of photoresist formed by EUV (extreme ultraviolet). These results were cross-validated through traditional GIWAXS (Grazing-incidence wide-angle X-ray scattering) and FTIR (Fourier transform infrared) analysis. s-SNOM is a useful tool for providing new insights into material analysis by visualizing nanoscale chemical information of local regions that conventional measurements could not confirm. © 2024 The Authors
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Article 2025-02-28
Observation of anomalous Nernst effect in non-collinear antiferromagnets
Ullah A.; Thi Nguyen T.-H.; Kim S.Curr. Appl. Phys. 2025; 70: 51-60Abstract : The field of spin caloritronics, which explores the interplay between spin current and thermal effects, is a promising path for new energy-efficient-electronic devices. However, current thermoelectric technologies are limited by conventional material choices and device designs. Antiferromagnetic materials, with their unique spin structure and magnetic characteristics, provide new opportunities for enhanced thermoelectric performance through spin-dependent effects. This review covers origin and measurement methodologies of anomalous Nernst effect, focusing on non-collinear antiferromagnets. By presenting insights into the relationship between electronic structure and thermoelectric performance as well as their practical measurements, this review aims to pave the way for developing AFM-based thermoelectric devices in advanced energy technologies. © 2024
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Article 2025-02-28
Oxidation effects on the optical and electrical properties of MoS2 under controlled baking temperatures
Jeong T.; Kim J.; Kim U.J.; Ji H.; Yun S.J.Curr. Appl. Phys. 2025; 70: 61-68Abstract : As silicon-based semiconductor technology scales down to the nanoscale, it encounters significant physical limitations, including reduced electron mobility, short-channel effects, and increased heat generation, which hinder device performance and reliability. Two-dimensional (2D) semiconductors, such as molybdenum disulfide (MoS2), offer great potential with superior electrical properties at the nanoscale, but the issue of excessive heat generation in highly integrated circuits persists. Therefore, it is essential to investigate the thermal durability of MoS2 under various heating conditions and its impact on physical properties and device performance. In this study, we systematically investigated the oxidation behavior and related physical property variations of CVD-grown MoS2 monolayers by baking them at different temperatures. It was clearly revealed that high-temperature baking induces p-doping and structural deformation, significantly altering optical and electrical properties. Despite the degradation in device performance, reduced interfacial Coulomb scattering was observed, suggesting potential for improved device stability. This study underscores the importance of understanding thermal stability to accelerate the development of 2D semiconductors for next-generation electronic devices. © 2024 Korean Physical Society
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Article 2025-02-28
Graphene/WS2/LaVO3 heterojunction for self-powered, high-speed, and broadband photodetectors
Shin D.H.; Lee H.Curr. Appl. Phys. 2025; 70: 69-75Abstract : Recently, there has been interest in developing high-performance self-driven photodetectors (PDs) using 2D-based heterostructures due to their unique optoelectronic properties. Here, we demonstrate that vertical-heterostructures based on graphene (Gr) transparent conductive electrodes, n-type 2D WS2, and p-type LaVO3 realize a broadband-responsive PD covering the wavelength range of 300–850 nm. Due to the formation of an electric field at the WS2/LaVO3 interface and the photovoltaic effect, this structure shows a rectifying operation with a maximum detectivity of 2.1 × 1010 Jones at zero bias. Additionally, it exhibits a fast fall time of 435 μs and a 3 dB bandwidth of 2300 Hz, making it suitable for high-speed self-powered optoelectronic applications. Therefore, the TETA-Gr/WS2/LaVO3 heterojunction is proposed as an excellent candidate for high-performance, self-powered, and broadband PDs. © 2024 Korean Physical Society
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Article 2025-02-28
Nanosecond electric pulse-induced ultrafast piezoelectric responses in Co3+ substituted BiFeO3 epitaxial thin films
Unithrattil S.; Min T.; Anoop G.; Lee J.Y.; kim T.Y.; Samanta S.; Qi Y.; Zhang J.; Hwang S.H.; Lee H.J.; Guo K.; Lee S.Y.; Imai Y.; Sakata O.; Shimizu K.; Shigematsu K.; Hojo H.; Yao K.; Azuma M.; Lee J.; Rappe A.M.; Jo J.Y.Curr. Appl. Phys. 2025; 70: 76-80Abstract : Understanding the ultra-fast dynamics of ferroelectric materials is essential for advancing the development of next-generation high speed electronic and photonic devices. Here, the ultrafast piezoelectric response of cobalt-substituted BiFeO3 (BiFe1-xCoxO3) with x = 0.15, consisting of morphotropic phase boundary of monoclinic MC and MA –type phases is investigated. The real-time piezoelectric response in (001)-oriented BiFe0.85Co0.15O3 (BFCO) epitaxial thin film was monitored using the time-resolved X-ray microdiffraction technique under an applied electric field with pulse widths 70 ns and 100 ns. The BFCO thin film yielded a high piezoelectric strain of approximately 0.53 % along [001] direction, with a giant c/a ratio (∼1.26) at an electric field of 1.3 MV/cm and a pulse width of 100 ns, with a piezoelectric coefficient (d33) of 40 pm/V. This finding is an important step towards the development of a high performance lead-free piezoelectric material for ultrafast operations in advanced technological applications. © 2024 Korean Physical Society
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Article 2025-02-28
Improved mobility in InAs nanowire FETs with sulfur-based surface treatment
Wu Y.H.; Kim H.H.; Shin J.C.Curr. Appl. Phys. 2025; 70: 81-86Abstract : InAs exhibits high electron mobility, positioning it as a promising candidate for advanced nanoelectronic device materials. Specifically, nanowire structures are particularly advantageous for electronic device applications, offering benefits such as reduced leakage current and minimized short-channel effects due to their distinctive one-dimensional electron transport characteristics. However, the large surface-to-volume ratio of the nanowires not only significantly degrades their electrical properties but also complicates the formation of semiconductor-metal ohmic contacts. In this study, surface treatments involving sulfur and (NH4)2S, along with rapid thermal annealing (RTA) processes, were applied to mitigate these disadvantages, resulting in a marked enhancement of the electrical properties of InAs nanowires. The electron mobility of the InAs nanowires was elevated from 83.06 cm2/V·s to 292.718 cm2/V·s through the application of passivation and RTA processes. © 2024
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Article 2025-02-28
A critical review of the refractory high-entropy materials: RHEA alloys, composites, ceramics, additively manufactured RHEA alloys
Guler S.H.; Yakin A.; Guler O.; Chattopadhyay A.K.; Simsek T.Curr. Appl. Phys. 2025; 70: 87-124Abstract : In this study, the traits, production methods, and applications of refractory high-entropy materials—including refractory high-entropy alloys (RHEAs), refractory high-entropy composites (RHE-Cs), and refractory high-entropy ceramics (RHE-Ce)—which are part of the broader category of refractory high-entropy materials with a wide range of applications, have been thoroughly examined and discussed. RHEAs have emerged as materials that exhibit superior properties, such as high melting temperatures, excellent temperature resistance, and high wear and corrosion resilience, in addition to high mechanical and fatigue strength. These attributes have made them extensively studied materials in recent times. The properties of RHEAs suggest their safe operation in challenging environments such as nuclear reactors, gas turbines, aerospace, and energy production. Among refractory materials, RHE-Cs stand out for their high strength and low density, showing significant potential for use in the automotive, aerospace, and space industries. Another group with a wide range of applications, RHE-Ce materials, is distinguished by their high-temperature resilience, high hardness, and low thermal conductivity, making them suitable for high-temperature environments. Refractory materials are generally fabricated using traditional techniques such as arc melting, powder metallurgy, and magnetron sputtering. In this study, along with traditional production methods, additive manufacturing techniques which have revolutionized the manufacturing field are discussed concerning their applications in refractory material production. Additive manufacturing methods enable the achievement of high temperatures and the production of homogeneous, single-phase solid solutions, making them suitable for fabricating refractory materials with high melting points. © 2024 Korean Physical Society
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February, 2025 | Volume 70
CAP Impact
• Journal Impact factor 2.4
• Elsevier Site Score 4.8
CAP Information
- 회수 : 월 1회
- 언어 : 영어
- 분야 : 응용물리학 전반
- 2001년부터 Current Applied Physics의 영문 국제학술지로 탄생.
- SCI에 등재된 국제학술지
- 인용지수 2.4 (2023년)
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pISSN 1226-4512
eISSN 2093-3827
