김명기 교수

Confining photons in the smallest possible volume has long been an objective of the nanophotonics community. In this Letter, we propose and demonstrate a three-dimensional (3D) gap-plasmon antenna that enables extreme photon squeezing in a 3D fashion with a modal volume of 1.3 × 10(-7) λ(3) (∼4 × 10 × 10 nm(3)) and an intensity enhancement of 400 000. A three-dimensionally tapered 4 nm air-gap is formed at the center of a complementary nanodiabolo structure by ion-milling 100 nm-thick gold film

We propose and demonstrate a direct integration of a wavelength-scale III–V nanolaser onto a silicon-on-insulator (SOI) waveguide. By employing high-precision microtransfer printing techniques, with an optimally designed photonic crystal nanolaser structure, we experimentally achieved a coupling efficiency of 83% between the InGaAsP nanobeam laser and the SOI waveguide. Our III–V nanobeam laser is designed as an asymmetric one-dimensional photonic crystal cavity, which allows unidirectional coup

Abstract Advanced electronics and telecommunication devices rely on electromagnetic (EM) waves of a wide frequency range during their operation, thereby necessitating the development of efficient and ultrathin materials for electromagnetic interference (EMI) shielding across multispectral EM waves, particularly those exceeding 100 GHz, equivalent to millimeter wavelengths. Here, this study reveals that highly crystalline Ti 3 C 2 T x MXene exhibits excellent EMI shielding performance across a mu

Despite growing ecological concerns, studies on microplastics and nanoplastics are still in their initial stages owing to technical hurdles in analytical techniques, especially for nanoplastics. We provide an overview of the general attributes of micro/nanoplastics in natural environments and analytical techniques commonly used for their analysis. After demonstrating the analytical challenges associated with the identification of nanoplastics due to their distinctive characteristics, we discuss

Abstract Detection of single nanoparticles or molecules has often relied on fluorescent schemes. However, fluorescence detection approaches limit the range of investigable nanoparticles or molecules. Here, we propose and demonstrate a non-fluorescent nanoscopic trapping and monitoring platform that can trap a single sub-5-nm particle and monitor it with a pair of floating nonlinear point sources. The resonant photon funnelling into an extremely small volume of ~5 × 5 × 7 nm 3 through the three-d

This study was designed to determine the appropriate application time of Kinesio taping for athletes to improve their maximum strength and to provide systematic information that can be widely applicable to the athletics, and consequently, to improve their performance in sports competitions. Ten healthy college students in the Department of Sport and Leisure Studies at ChoongNam were screened, and individuals with a history of previous injury or surgery in their nerve, muscle, and skeletal system

Metasurface technology is revolutionizing the field of optics and pursuing expanded functions via technical developments, such as the integration of multiple metasurfaces with optical fibers. Despite several attempts to realize metasurface-on-fiber platforms, negligible fiber-facet areas pose a serious obstacle to efficient and precise fabrication. Herein, we demonstrate a novel sequential micro-punching process that enables rapid and precise stacking of multiple polymer metasurfaces on the end

Abstract Surface plasmons in 2D materials such as graphene exhibit exceptional field confinement. However, the low electron density of majority of 2D materials, which are semiconductors or semimetals, has limited their plasmons to mid‐wave or long‐wave infrared regime. This study demonstrates that a 2D Ti 3 C 2 T x MXene with high electron density can not only support strong plasmon confinement with an acoustic plasmon mode in the short‐wave infrared region, but also provide ultrahigh nonlinear

Abstract Two-dimensional (2D) MXenes have attracted significant attention in electromagnetic interference (EMI) shielding applications due to their excellent metallic conductivity, high surface area, 2D geometry, tunable surface chemistry, and solution processability. In this study, we present a straightforward way of introducing multiple nanoscale interfaces into Ti 3 C 2 T x MXenes using insulating graphene oxide (GO) intercalants to enhance internal scattering, resulting in improved EMI shiel

This purpose of this study was to examine the influence of age and gender on whole and body regional muscle mass and distribution using dual energy X-ray absorptiometry(DEXA). The subjects consisted of healthy adult men and women who had participated in body composition studies at Korea University. The subjects varied in age(20～73 yr) and body mass index(15.6～42.5). None of the subjects was taking medications known to affect the study variables. They were divided three groups according to age.

본 연구는 60세 이상의 노인 여성을 대상으로 12주간의 중저강도 댄스스포츠 프로그램을 실시하였을 때 생리적 기능, 정신건강 및 지각된 건강상태에 미치는 영향을 비교하여 노년기의 댄스스포츠 프로그램의 적용 효과를 규명하기 위한 것이다. 규칙적인 댄스스포츠 프로그램을 실시 후 노인의 생리적 기능과 관련된 변인 중 안정시 혈압(수축기, 이완기), 안정시 심박수는 집단간 유의한 차이가 없었고(p> 0.5) 체지방률은 유의한 차이를 나타냈다(p< 0.5). 또한 정신건강진단 점수의 총점은 실험군과 대조군간의 유의한 차이를 나타냈고(p< 0.5), 지각된 건강상태 점수는 실험군과 대조군간의 유의한 차이를 나타났다(p< 0.5). 즉 규칙적인 댄스스포츠 프로그램는 60세 이상 노인의 생리적 기능과 정신건강 및 지각된 건강상태에 긍정적으로 영향을 미친 것으로 나타났다. 따라서 규칙적인 댄스스포츠 프로그램은 노인여성의 신체적정신적 건강에 도움을 주는 좋은 운동프로그램으로 제시할 수 있다.

The purpose of this research is to prepare exercise stability/safety by predicting possible dangerous situations during competitions in advance and presenting appropriate exercise intensity based on TCD(Transcranial Doppler ultrasound) analysis of Systolic, Diastolic and Mean Blood Flow Velocity, Pulsatility Index(PI) and Resistive Index(RI) from MCA according to exercise intensity as well as at rest. The subjects were 10(ten) Soccer and Judo players respectively from high school over 5 years in