Sang Yun LEE
Yonsei University · 工学
研究室紹介
Professor Sang Yun Lee's research lab specializes in quantum materials and nanoscale devices, with a focus on color centers in wide-bandgap semiconductors—particularly silicon-vacancy centers in silicon carbide—for quantum information and sensing applications. The lab explores spin-optical interfaces, quantum coherence, and charge state control in solid-state systems to enable scalable quantum networks. Additionally, the group investigates advanced oxide dielectrics and metal-insulator-metal capacitors for next-generation nanoelectronics, while also contributing to quantum metrology and biophotonics through quantitative phase imaging of biological cells. Their interdisciplinary work bridges quantum physics, materials science, and biomedical engineering.
Research Overview
Research Output Trend
Figures are computed from collected data and may differ slightly.
Selected Papers
15Abstract Scalable quantum networking requires quantum systems with quantum processing capabilities. Solid state spin systems with reliable spin–optical interfaces are a leading hardware in this regard. However, available systems suffer from large electron–phonon interaction or fast spin dephasing. Here, we demonstrate that the negatively charged silicon-vacancy centre in silicon carbide is immune to both drawbacks. Thanks to its 4 A 2 symmetry in ground and excited states, optical resonances are
A metal–insulator–metal (MIM) capacitor using ZrO2 on tungsten (W) metal bottom electrode was demonstrated and characterized in this letter. Both ZrO2 and W metal were synthesized by an atomic layer deposition (ALD) method. High-quality 110∼115 Å ZrO2 films were grown uniformly on ALD W using ZrCl4 and H2O precursors at 300 °C, and polycrystalline ZrO2 in the ALD regime could be obtained. A 13∼14-Å-thick interfacial layer between ZrO2 and W was observed after fabrication, and it was identified a
The weak value concept has enabled fundamental studies of quantum measurement and, recently, found potential applications in quantum and classical metrology. However, most weak value experiments reported to date do not require quantum mechanical descriptions, as they only exploit the classical wave nature of the physical systems. In this work, we demonstrate measurement of the sequential weak value of two incompatible observables by making use of two-photon quantum interference so that the resul
Color centers with long-lived spins are established platforms for quantum sensing and quantum information applications. Color centers exist in different charge states, each of them with distinct optical and spin properties. Application to quantum technology requires the capability to access and stabilize charge states for each specific task. Here, we investigate charge state manipulation of individual silicon vacancies in silicon carbide, a system which has recently shown a unique combination of
ABSTRACT: A descriptive vocabulary was developed to fully describe the sensory characteristics of soymilks. Five commercial soymilks and 1 laboratory‐prepared soymilk were used in the study. Nine subjects participated in 8 round‐table discussions to develop descriptive language and references. The 6 soymilks were evaluated in 4 replications using this language. Principal component analysis was conducted on the resulting data to eliminate redundant terms and differentiate between samples. Thirty‐
Here, we report the results of a study on the effects of ethanol exposure on human red blood cells (RBCs) using quantitative phase imaging techniques at the level of individual cells. Three-dimensional refractive index tomograms and dynamic membrane fluctuations of RBCs were measured using common-path diffraction optical tomography, from which morphological (volume, surface area, and sphericity); biochemical (hemoglobin (Hb) concentration and Hb content); and biomechanical (membrane fluctuation)
Electronic spin systems with $\mathrm{S}>1/2$ provide an efficient method for dc vector magnetometry, since the conventional electron spin resonance spectra at a given magnetic field reflect not only the field strength but also orientation in the presence of strong spin-spin interactions. $S=1$ spins, e.g., the nitrogen-vacancy centers in diamond, have been intensively investigated for such a purpose. In this report, we compare $S=1$ and $3/2$ spins, and discuss how one can apply general prin
An appealing avenue for organic spintronics lies in direct coherent control of the spin population by means of pulsed electron spin resonance techniques. Whereas previous work has focused on the electrical detection of coherent spin dynamics, we demonstrate here the equivalence of an all-optical approach, allowing us to explore the influence of materials chemistry on the spin dynamics. We show that deuteration of the conjugated polymer side groups weakens the local hyperfine fields experienced b
Optical measurements of the morphological and biochemical imaging of phytoplankton are presented. Employing quantitative phase imaging techniques, 3-D refractive index maps and high-resolution 2-D quantitative phase images of individual live phytoplankton are simultaneously obtained without exogenous labeling agents. In addition, biochemical information of individual phytoplankton including volume, mass, and density of individual phytoplankton are also quantitatively obtained from the measured r
Abstract Two groups of closely associated, peraluminous, two-mica granitic gneiss were identified in the area. The older, sparsely distributed unit is equigranular (EG) with initial εNd ∼ − 8·8 and initial 87Sr/86Sr ∼0·7098. Its age is uncertain. The younger unit is Late Cretaceous (∼80 Ma), pegmatitic, and sillimanite-bearing (KPG), with εNd from −15·8 to −17·3 and initial 87Sr/86Sr from 0·7157 to 0·7198. The concentrations of Fe, Mg, Na, Ca, Sr, V, Zr, Zn and Hf are higher, and K, Rb and Th ar
Organic-inorganic hybrid perovskites have been investigated extensively for use in perovskite-based solar cells and light-emitting diodes (LEDs) because of their excellent electrical and optical properties. Although the flexibility of perovskite LEDs has been studied through empirical methods such as cyclic bending tests, the flexibility of the perovskite layer has not been investigated systemically. Here, flexible and semitransparent perovskite LEDs are fabricated: a PEDOT:PSS anode and Ag nano
ABSTRACT: : Four different whey‐protein‐isolate (WPI)/plasticizer formulations were compared to determine which provided the most gloss and which was most stable with time when applied on chocolates. The 4 plasticizers studied were glycerol, polyethylene glycol 400 (PEG 400), propylene glycol (PG), and sucrose, all in a 1:1 ratio with WPI. Gloss stability was determined by measuring gloss fade over time using the Tricor Gloss Analysis System. WPI/sucrose coatings provided the highest and most st
Continuous-wave optically and electrically detected magnetic resonance spectroscopy (cwODMR/cwEDMR) allow the investigation of paramagnetic states involved in spin-dependent transitions, like recombination and transport. Although experimentally similar to conventional electron spin resonance (ESR), there exist limitations when applying models originally developed for ESR to observables (luminescence and electric current) of cwODMR and cwEDMR. Here we present closed-form solutions for the modulat