Prof. Junsuk Rho Profile

Prof. Junsuk Rho

at Pohang Univ of Science and Technology

SPIE Involvement:

Scholarship Committee | Conference Program Committee | Editorial Board Member: Advanced Photonics Nexus | Editorial Board Member: Photonics Insights | Author

Publications (65)

SPIE Journal Paper | 14 November 2024 Open Access

Open Access

Deep-learning-driven end-to-end metalens imaging

Joonhyuk Seo, Jaegang Jo, Joohoon Kim, Joonho Kang, Chanik Kang, Seong-Won Moon, Eunji Lee, Jehyeong Hong, Junsuk Rho, Haejun Chung

AP, Vol. 6, Issue 06, 066002, (November 2024) https://doi.org/10.1117/12.10.1117/1.AP.6.6.066002

KEYWORDS: Image restoration, Imaging systems, Metalenses, Image quality, Education and training, Point spread functions, Chromatic aberrations, RGB color model, Object detection, Image resolution

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SPIE Journal Paper | 26 June 2024 Open Access

Open Access

Iso-propagation vortices: a breakthrough in optical communication technology

Cherry Park, Junsuk Rho

AP, Vol. 6, Issue 03, 030503, (June 2024) https://doi.org/10.1117/12.10.1117/1.AP.6.3.030503

KEYWORDS: Quantum optical communication, Beam divergence, Telecommunications, Multiplexing, Free space optics, Optical transmission, Atmospheric propagation, Quantum receivers, Quantum numbers, Quantum channels

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Proceedings Article | 11 June 2024 Presentation

Presentation

Low-cost and scalable manufacturing of optical metasurfaces in the visible using engineered optical materials

Junsuk Rho

Proceedings Volume PC12990, PC129901C (2024) https://doi.org/10.1117/12.3014260

KEYWORDS: Manufacturing, Optics manufacturing, Optical engineering, Printing, Dielectrics, Atomic layer deposition, Zirconium dioxide, Visible radiation, Refractive index, Holography

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SPIE Journal Paper | 7 June 2024 Open Access

Open Access

Structural coloration: advancements and challenges

Dohyun Kang, Junsuk Rho

PI, Vol. 3, Issue 02, C04, (June 2024) https://doi.org/10.1117/12.10.3788/PI.2024.C04

KEYWORDS: Nanoimprint lithography, Near eye displays, Localized surface plasmon resonances, Fabrication, Design, Commercialization, Nanostructures, Humidity, Sensors, Light emitting diodes

Proceedings Article | 6 June 2024 Poster

Poster

Humidity-sensitive polyvinyl alcohol metasurfaces for realizing advanced optical security

Byoungsu Ko, Trevon Badloe, Younghwan Yang, Junsuk Rho

Proceedings Volume PC12990, PC129901Z (2024) https://doi.org/10.1117/12.3022774

KEYWORDS: Polyvinyl alcohol, Information security, Humidity, Relative humidity, Printing, Platinum, Nanoimprint lithography, Holography, Computer security, Thin films

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Proceedings Article | 13 March 2024 Presentation

Presentation

Metasurface for full-space structured light and dynamic imaging system for compact nanophotonic device

Yeseul Kim, Junsuk Rho, Trevon Badloe, Joohoon Kim, Inki Kim

Proceedings Volume PC12897, PC128970A (2024) https://doi.org/10.1117/12.3001376

KEYWORDS: Structured light, Nanophotonics, Imaging systems, Point clouds, Optical components, Virtual reality, System integration, Structural design, Sensing systems, Polarization

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Proceedings Article | 13 March 2024 Presentation

Presentation

Wavelength-multiplexed orbital angular momentum meta-holography

Jaehyuck Jang, Junsuk Rho, Seong-Won Moon, Joohoon Kim

Proceedings Volume PC12897, PC1289708 (2024) https://doi.org/10.1117/12.3001275

KEYWORDS: Angular momentum, Holography, Volume holography, Video coding, Video, Switching, Holograms, Design and modelling, Crosstalk, Color

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Proceedings Article | 13 March 2024 Poster

Poster

Nonlocal metasurface fabricated by quantum dot embedded resin printing

Huichang Yun, Minsu Jeong, Junsuk Rho

Proceedings Volume PC12896, PC128961H (2024) https://doi.org/10.1117/12.3002154

KEYWORDS: Quantum dots, Nanolithography, Printing, Polarization, Emission wavelengths, Refractive index, Nanostructures, Flat optics, Titanium dioxide, Titanium

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Proceedings Article | 13 March 2024 Presentation

Presentation

Design, materials, and manufacturing of optical metasurfaces for flat optics, devices, and applications

Jeong-Geun Yun, Hyunjung Kang, Dohyun Kang, Joohoon Kim, Gyeongtae Kim, Junsuk Rho

Proceedings Volume PC12897, PC128970F (2024) https://doi.org/10.1117/12.2691989

KEYWORDS: Waveguides, Augmented reality, Design and modelling, Glasses, Displays, Wave propagation, Refractive index, Optical gratings, Optical design, Optical components

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Proceedings Article | 13 March 2024 Presentation

Presentation

Nanoimprinted photonic crystal using quantum dot embedded resin

Minsu Jeong, Junsuk Rho

Proceedings Volume PC12896, PC128960U (2024) https://doi.org/10.1117/12.3001301

KEYWORDS: Photonic crystals, Quantum dots, Photonic nanostructures, Composite resins, Titanium dioxide, Resonators, Quantum limits, Photons, Nanophotonics, Nanoparticles

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Proceedings Article | 13 March 2024 Poster

Poster

Enhanced upconversion vortex emission using bound state in continuum

Minsu Jeong, Junsuk Rho

Proceedings Volume PC12896, PC128961G (2024) https://doi.org/10.1117/12.3001304

KEYWORDS: Photons, Upconversion, Near infrared, Polarization, Visible radiation, Photonic crystals, Photon polarization, Photoluminescence, Phase distribution, Optical properties

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Proceedings Article | 12 March 2024 Presentation + Paper

Presentation + Paper

3D laser-nanoprinted meta-optics: a breakthrough photonic platform for wavefront shaping and molecular sensing

Haoran Ren, Chenhao Li, Andreas Aigner, Jaehyuck Jang, Junsuk Rho, Markus Schmidt, Stefan Maier

Proceedings Volume 12901, 1290109 (2024) https://doi.org/10.1117/12.3008920

KEYWORDS: Structured light, Quantum light, Wavefronts, Molecular photonics, Laser applications, Molecular lasers, 3D surface sensing, Structured optical fibers, Wavefront sensors, Optical fibers

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Proceedings Article | 6 October 2023 Poster

Poster

Gap-plasmon-driven liquid-crystal integrated chiral metasurface for intensity tunable hologram at the visible frequencies

Younghwan Yang, Hongyoon Kim, Junsuk Rho

Proceedings Volume PC12646, PC126461N (2023) https://doi.org/10.1117/12.2672556

KEYWORDS: Liquid crystals, Reflection, Polarization, Holography, Holograms, Dichroic materials, Split ring resonators, Polarized light, Nanostructures, Visible radiation

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Proceedings Article | 6 October 2023 Poster

Poster

Observing sequential aspects of metasurface with deep neural networks

Jaebum Noh, Younghwan Yang, Junsuk Rho

Proceedings Volume PC12655, PC1265517 (2023) https://doi.org/10.1117/12.2676322

KEYWORDS: Neural networks, Design and modelling, Refractive index, Visible radiation, Reflection, Optical transmission, Optical properties, Network architectures, Nanophotonics, Holograms

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Proceedings Article | 6 October 2023 Poster

Poster

Structural coloration using bandgap engineered, low-optical losses hydrogenated amorphous silicon

Younghwan Yang, Jaehyuck Jang, Chunghwan Jung, Trevon Badloe, Junsuk Rho

Proceedings Volume PC12646, PC126461O (2023) https://doi.org/10.1117/12.2673186

KEYWORDS: Amorphous silicon, Titanium dioxide, Refractive index, Gallium nitride, Visible radiation, Toxicity, Silicon nitride, Semiconductors, Scattering, Reflection

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Proceedings Article | 5 October 2023 Presentation

Presentation

Perspectives of design, materials, and fabrication for metasurfaces

Junsuk Rho

Proceedings Volume PC12648, PC126480G (2023) https://doi.org/10.1117/12.2672096

KEYWORDS: Design and modelling, Materials processing, Printing, Visible radiation, Photonics, Holography, Amorphous silicon, Zirconium dioxide, Ultraviolet radiation, Physics

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Proceedings Article | 5 October 2023 Presentation

Presentation

Deep learning enabled control of active metasurface antenna

Jaebum Noh, Junsuk Rho

Proceedings Volume PC12655, PC126550S (2023) https://doi.org/10.1117/12.2676330

KEYWORDS: Antennas, Neural networks, Deep learning, Education and training, PIN photodiodes

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Proceedings Article | 5 October 2023 Poster

Poster

Transparent radiative cooling with non-diffractive perforated-mirror structure

Byoungsu Ko, Jaebum Noh, Junsuk Rho

Proceedings Volume PC12653, PC126530D (2023) https://doi.org/10.1117/12.2676289

KEYWORDS: Reflection, Transparency, Reflectors, Visible radiation, Solar energy, Mirrors, Visibility, Solar energy systems, Light absorption, Energy efficiency

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Proceedings Article | 4 October 2023 Presentation

Presentation

Principle and applications of metasurfaces to enhance the spin Hall effect of light

Junsuk Rho

Proceedings Volume PC12647, PC1264715 (2023) https://doi.org/10.1117/12.2675535

KEYWORDS: Polarized light, Sensing systems, Photonics, Refraction, Reflection, Precision measurement, Polarization, Phase modulation, Optical properties, Nanophotonics

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Proceedings Article | 4 October 2023 Presentation

Presentation

Bandgap engineered low-loss a-Si:H for efficient dielectric metasurfaces at visible frequencies

Younghwan Yang, Gwanho Yoon, Minkyung Kim, Dasol Lee, Junsuk Rho

Proceedings Volume PC12646, PC126460F (2023) https://doi.org/10.1117/12.2672557

KEYWORDS: Dielectrics, Refractive index, Phase measurement, Optical components, Miniaturization, Incident light, Engineering, Chemical vapor deposition, Amorphous silicon

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Proceedings Article | 4 October 2023 Presentation

Presentation

Humidity-responsive full color nano-pixels via nanoporous Fabry-Pérot structure

Jaekyung Kim, Byoungsu Ko, Younghwan Yang, Junsuk Rho

Proceedings Volume PC12646, PC126460B (2023) https://doi.org/10.1117/12.2677174

KEYWORDS: Humidity, Silver, Polyvinyl alcohol, Nanoparticles, Metals, Toxicity, Optical properties, Nanoimprint lithography, Molecules, Magnetism

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Proceedings Article | 4 October 2023 Poster

Poster

Electrochemically modulated structural color filter with polarization sensitive transmission

Jaekyung Kim, Junsuk Rho

Proceedings Volume PC12647, PC126471V (2023) https://doi.org/10.1117/12.2677179

KEYWORDS: Optical filters, Polarization, Optical transmission, Gold, Mirrors, Refractive index, Modulation, Electrooptic modulation, Electro optics, Tunable filters

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Proceedings Article | 4 October 2023 Presentation

Presentation

Humidity-responsive tunable metasurfaces with nanoimprinted structural polyvinyl alcohol

Byoungsu Ko, Trevon Badloe, Younghwan Yang, Junsuk Rho

Proceedings Volume PC12646, PC126460G (2023) https://doi.org/10.1117/12.2676288

KEYWORDS: Polyvinyl alcohol, Optical components, Humidity, Relative humidity, Nanostructures, Visible radiation, Structural design, Polymers, Optical properties, Optical image encryption

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Proceedings Article | 28 September 2023 Presentation

Presentation

Cascade domino lithography for extreme photon squeezing at the sub-nanometer scale

Junsuk Rho

Proceedings Volume PC12657, PC1265707 (2023) https://doi.org/10.1117/12.2676403

KEYWORDS: Quantum plasmonics, Lithography, Quantum squeezing, Quantum enhancement, Surface enhanced Raman spectroscopy, Raman spectroscopy, Quantum control, Gold, Excitons, Control systems

Read Abstract +

Squeezing light into deep sub-wavelength volumes or even into few-nanometer gaps has led to the investigation of interesting phenomena, including strong coupling, quantum plasmonics, nonlinearity enhancement, nonlocality, and molecular junctions. Bowtie nanoantennas, as a common configuration for plasmonic nanocavity, have been extensively studied owing to their great enhancement of the localized field. The enhancement rapidly increases as the tips become sharper and the gap becomes narrower. However, every effort paid to increase the extreme sharpness and nanomete rprecision of less than 10 nm gaps result in the downfall of fabrication throughput, since it relies on the probability of achieving one satisfactory piece out of the many fabricated. Here, an intuitive “fall-to-rise” schemes are proposed and experimentally validated using cascade domino lithography (CDL) and capillary-force-induced collapse lithography(CCL). In this report, we successfully establish a controllable lithography method of making extremely sharp bowtie-shaped plasmonic nanocavity with sub-1nm radius curvature reaching the size of a gold nanocluster as well as a single-digit-nanometer gap between such sharp tips. By controlling falling mechanisms of photoresist mask structures, a facileroute to fabricate sub-10 nm plasmonic nanocavity with high yield is provided. In addition, a proof-of-concep tapplication in surface enhanced Raman spectroscopy (SERS) is demonstrated. The numerically calculated intensity enhancement is over 2.2×10^4 with the confined mode volume below 7.14×10^-6 λ^3, the measured average Raman enhancement factor is of the order of 10^6 with the calculated local Raman enhancement factor over 10^8 promising for single-molecular level sensing applications. Furthermore, such sharp plasmonic nanocavity is used to probe and control localized excitons at room temperature, which offers new strategies for active quantum nano-optical devices.Atomically thin semiconductors, WSe2, are coated on top of plasmonic nanocavity and Au tip for tip-enhanced photo luminescence (TEPL) spectroscopy is added to induce tensile strain in the nanoscale region to create robust localized exciton at the hotspot region. Such an approach provides a systematic way to control localized quantum light.This controlling mechanism of nanostructures falling opens up an unexplored gateway towards conquering the limitations of exploring the realm of plasmonics down to the sub-nanometer regime.

SPIE Journal Paper | 17 July 2023 Open Access

Open Access

Advent of torsional optomechanics from Beth’s legacy

Jaehyuck Jang, Jungho Mun, Junsuk Rho

AP, Vol. 5, Issue 04, 040501, (July 2023) https://doi.org/10.1117/12.10.1117/1.AP.5.4.040501

KEYWORDS: Angular momentum, Optomechanical design, Acoustics, Quantum spin, Quantum fields, Quantum optics experiments, Quantum light, Quantum detection, Printed circuit board testing, Pendulums

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SPIE Journal Paper | 4 July 2023 Open Access

Open Access

Optical Orbital Angular Momentum: Thirty Years and Counting

Guixin Li, Junsuk Rho, Xiao-Cong Yuan

AP, Vol. 5, Issue 03, 030101, (July 2023) https://doi.org/10.1117/12.10.1117/1.AP.5.3.030101

KEYWORDS: Angular momentum, Quantum photonics, Structured light, Quantum light generation, Phase interferometry, Pendulums, Optical parametric oscillators, Optical interconnects, Multiplexing, Lithium

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SPIE Journal Paper | 7 June 2023 Open Access

Open Access

Writing nanometer-scale structures for centimeter-scale color printing

Younghwan Yang, Trevon Badloe, Junsuk Rho

AP, Vol. 5, Issue 03, 030501, (June 2023) https://doi.org/10.1117/12.10.1117/1.AP.5.3.030501

KEYWORDS: Fabrication, Multiphoton lithography, Color printing, Spatial resolution, RGB color model, Pixel resolution, Photoresist materials, Optical filters, Nanoimprint lithography, Lithography

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SPIE Journal Paper | 22 May 2023 Open Access

Open Access

Emerging low-cost, large-scale photonic platforms with soft lithography and self-assembly

Hyunjung Kang, Dohyeon Lee, Younghwan Yang, Dong Kyo Oh, Junhwa Seong, Jaekyung Kim, Nara Jeon, Dohyun Kang, Junsuk Rho

PI, Vol. 2, Issue 02, R04, (May 2023) https://doi.org/10.1117/12.10.3788/PI.2023.R04

KEYWORDS: Block copolymers, Particles, Nanoimprint lithography, Printing, Lithography, Fabrication, Polymers, Gold, Optical lithography, Copyright

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Proceedings Article | 17 March 2023 Presentation

Presentation

Dynamic metasurfaces for holography and structural coloration

Junsuk Rho

Proceedings Volume PC12432, PC124320V (2023) https://doi.org/10.1117/12.2647173

KEYWORDS: Refractive index, Holography, Liquid crystals, Optical filters, Solid state electronics, Information security, Humidity, Holograms, Gas sensors, Video

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Proceedings Article | 17 March 2023 Presentation

Presentation

Multiplexing molecular spectroscopy via metasurface using plasmonic resonance energy transfer

Hongyoon Kim, Inki Kim, Seungyeon Han, Joohoon Kim, Yangkyu Kim, Inhee Choi, Junsuk Rho, Luke Lee

Proceedings Volume PC12432, PC124320L (2023) https://doi.org/10.1117/12.2647810

KEYWORDS: Plasmonics, Resonance energy transfer, Nanoparticles, Multiplexing, Scattering, Molecular spectroscopy, Absorption, Plasmons, Resonance enhancement, Light scattering

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Proceedings Article | 17 March 2023 Presentation

Presentation

Deep learning-based glucose sensing robust to sample position error with split ring resonator sensor

Seokho Lee, Trevon Badloe, Younghwan Yang, Junsuk Rho

Proceedings Volume PC12432, PC124320M (2023) https://doi.org/10.1117/12.2648302

KEYWORDS: Refractive index, Data processing, Water, Visualization, Optical properties, Scattering, Optical signal processing, Nanostructures, Information visualization, Holograms

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Proceedings Article | 14 March 2023 Poster

Poster

Disordered plasmonic nanoparticle-driven etalon for colorimetric gas sensor

Chunghwan Jung, Jaehyuck Jang, Junsuk Rho

Proceedings Volume 12417, 124171A (2023) https://doi.org/10.1117/12.2658444

KEYWORDS: Plasmonics, Gas sensors, Fabry–Perot interferometers, Ultrafast phenomena, Nanoparticles, Sensors, Resonators, Refractive index, Reflectivity, Optical properties

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Proceedings Article | 9 March 2023 Poster + Paper

Poster + Paper

Tapered fiber-based shear force scanning photoacoustic microscopy

Moongyu Han, Byullee Park, Hongyoon Kim, Jinhee Yoo, Dong Kyo Oh, Seongwon Moon, Joongho Ahn, Hae Gyun Lim, Inki Kim, Hyung Ham Kim, Junsuk Rho, Chulhong Kim

Proceedings Volume 12379, 123791H (2023) https://doi.org/10.1117/12.2648171

KEYWORDS: Gold, Near field, Glasses, Photoacoustic microscopy, Aluminum, Photoacoustic spectroscopy, Near field optics, Image resolution, Wave propagation, Ultrasonography

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SPIE Journal Paper | 21 December 2022 Open Access

Open Access

Computation at the speed of light: metamaterials for all-optical calculations and neural networks

Trevon Badloe, Seokho Lee, Junsuk Rho

AP, Vol. 4, Issue 06, 064002, (December 2022) https://doi.org/10.1117/12.10.1117/1.AP.4.6.064002

KEYWORDS: Artificial neural networks, Photonic metamaterials, Optical metamaterials, Design and modelling, Reflection, Edge detection, Education and training, Computing systems, Image processing, Copyright

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Proceedings Article | 4 October 2022 Presentation

Presentation

Suppressing optical losses of hydrogenated amorphous silicon for dielectric metasurfaces working at the visible frequencies, and revealing its structural disorder. (Conference Presentation)

Younghwan Yang, Gwanho Yoon, Sunghak Park, Ki Tae Nam, Junsuk Rho

Proceedings Volume PC12202, PC1220206 (2022) https://doi.org/10.1117/12.2632722

KEYWORDS: Dielectrics, Visible radiation, Amorphous silicon, Refractive index, Plasma enhanced chemical vapor deposition, Titanium dioxide, Silicon, Gallium nitride, Semiconductors, Plasma

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Proceedings Article | 3 October 2022 Presentation

Presentation

Electrically tunable intensity of metaholography using liquid-crystal assisted chiral metasurfaces at the visible

Younghwan Yang, Hongyoon Kim, Junsuk Rho

Proceedings Volume PC12195, PC121950K (2022) https://doi.org/10.1117/12.2632939

KEYWORDS: Liquid crystals, Split ring resonators, Polarization, Plasmonics, Dichroic materials, Switches, Silicon, Integrated optics, Germanium, Amorphous silicon

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Proceedings Article | 3 October 2022 Presentation

Presentation

Tunable one-step nanoimprinted RGB-achromatic bifocal metalens (Conference Presentation)

Trevon Badloe, Sunae So, Joohoon Kim, Younghwan Yang, Jaekyung Kim, Yeseul Kim, Junsuk Rho

Proceedings Volume PC12195, PC121951M (2022) https://doi.org/10.1117/12.2632895

KEYWORDS: Wave propagation, Virtual reality, Titanium dioxide, Optical components, Nanoparticles, Optical properties, Liquid crystals, Lenses, LCDs

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Proceedings Article | 3 October 2022 Presentation

Presentation

One-step nanoimprinting of PVA for dynamic dual-mode security metasurfaces

Trevon Badloe, Byoungsu Ko, Younghwan Yang, Junsuk Rho

Proceedings Volume PC12196, PC121961A (2022) https://doi.org/10.1117/12.2632909

KEYWORDS: Information security, Humidity, Holography, Wavefronts, Visible radiation, Refractive index, Receivers, Printing, Packaging, Optical properties

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Proceedings Article | 3 October 2022 Presentation

Presentation

Ultrafast colorimetric vapor sensors with disordered plasmonic nanoparticles

Jaehyuck Jang, Chunghwan Jung, Soo-Jung Kim, Sung-Hoon Hong, Junsuk Rho

Proceedings Volume PC12197, PC121970B (2022) https://doi.org/10.1117/12.2632727

KEYWORDS: Sensors, Fabry–Perot interferometers, Plasmonics, Nanoparticles, Ultrafast phenomena, Humidity, Metals, Polymers, Molecules, Image sensors

Read Abstract +

Proceedings Article | 3 October 2022 Presentation

Presentation

A dispersion-engineered metafiber for broadband and polarization-insensitive focusing and imaging over the entire telecommunication range (Conference Presentation)

Jaehyuck Jang, Haoran Ren, Chenhao Li, Junsuk Rho, Markus Schmidt, Stefan Maier

Proceedings Volume PC12195, PC121951K (2022) https://doi.org/10.1117/12.2632721

KEYWORDS: Telecommunications, In vivo imaging, Wet etching, Photonics, Phase shift keying, Optical tweezers, Optical fibers, Modulation, GRIN lenses, Fiber lasers

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Proceedings Article | 3 October 2022 Presentation

Presentation

Realization of ultra-sharp plasmonic nanocavity for extreme photon squeezing via collapse control

Junsuk Rho

Proceedings Volume PC12197, PC121970D (2022) https://doi.org/10.1117/12.2632280

KEYWORDS: Plasmonics, Lithography, Photonic nanostructures, Excitons, Surface enhanced Raman spectroscopy, Raman spectroscopy, Gold, Control systems, Spectroscopes, Semiconductors

Read Abstract +

Squeezing light into deep sub-wavelength volumes or even into few-nanometer gaps has led to the investigation of interesting phenomena, including strong coupling, quantum plasmonics, nonlinearity enhancement, nonlocality, and molecular junctions. Bowtie nanoantennas, as a common configuration for plasmonic nanocavity, have been extensively studied owing to their great enhancement of the localized field. The enhancement rapidly increases as the tips become sharper and the gap becomes narrower. However, every effort paid to increase the extreme sharpness and nanometer precision of less than 10 nm gaps result in the downfall of fabrication throughput, since it relies on the probability of achieving one satisfactory piece out of the many fabricated. Here, an intuitive “fall-to-rise” schemes are proposed and experimentally validated using cascade domino lithography (CDL) and capillary-force-induced collapse lithography (CCL). In this report, we successfully establish a controllable lithography method of making extremely sharp bowtie-shaped plasmonic nanocavity with sub-1nm radius curvature reaching the size of a gold nanocluster as well as a single-digit-nanometer gap between such sharp tips. By controlling falling mechanisms of photoresist mask structures, a facile route to fabricate sub-10 nm plasmonic nanocavity with high yield is provided. In addition, a proof-of-concept application in surface enhanced Raman spectroscopy (SERS) is demonstrated. The numerically calculated intensity enhancement is over 2.2×10^4 with the confined mode volume below 7.14×10^-6 λ^3, the measured average Raman enhancement factor is of the order of 10^6 with the calculated local Raman enhancement factor over 10^8 promising for single-molecular level sensing applications. Furthermore, such sharp plasmonic nanocavity is used to probe and control localized excitons at room temperature, which offers new strategies for active quantum nano-optical devices. Atomically thin semiconductors, WSe2, are coated on top of plasmonic nanocavity and Au tip for tip-enhanced photoluminescence (TEPL) spectroscopy is added to induce tensile strain in the nanoscale region to create robust localized exciton at the hotspot region. Such an approach provides a systematic way to control localized quantum light. This controlling mechanism of nanostructures falling opens up an unexplored gateway towards conquering the limitations of exploring the realm of plasmonics down to the sub-nanometer regime.

SPIE Journal Paper | 7 March 2022 Open Access

Open Access

Tunable metasurfaces towards versatile metalenses and metaholograms: a review

Jaekyung Kim, Junhwa Seong, Younghwan Yang, Seong-Won Moon, Trevon Badloe, Junsuk Rho

AP, Vol. 4, Issue 02, 024001, (March 2022) https://doi.org/10.1117/12.10.1117/1.AP.4.2.024001

KEYWORDS: Holograms, Holography, Polarization, Modulation, Liquid crystals, Dielectric polarization, Light sources, Graphene, 3D image reconstruction, Photonics

Read Abstract +

Proceedings Article | 5 March 2021 Presentation

Presentation

Single-step manufacturing of high-efficiency dielectric metasurfaces and metalenses

Junsuk Rho, Gwanoho Yoon

Proceedings Volume 11696, 116960A (2021) https://doi.org/10.1117/12.2582410

KEYWORDS: Dielectrics, Manufacturing, Titanium dioxide, Nanoparticles, Nanofabrication, Thin film deposition, Printing, Plasmonics, Optical properties, Optical lithography

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Proceedings Article | 5 March 2021 Poster

Poster

Selective multilayer emitter for high performance daytime radiative cooling

Sunae So, Younghwan Yang, Junsuk Rho

Proceedings Volume 11681, 1168113 (2021) https://doi.org/10.1117/12.2583040

KEYWORDS: Transparency, Structural design, Solar radiation, Solar energy, Silica, Magnesium fluoride, Genetic algorithms, Atmospheric modeling, Absorption

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Proceedings Article | 5 March 2021 Presentation

Presentation

Multipole approach for light-matter interaction involving structured optical fields and meta-atoms

Jungho Mun, Junsuk Rho

Proceedings Volume 11701, 117010G (2021) https://doi.org/10.1117/12.2583320

KEYWORDS: Light-matter interactions, Dichroic materials, Polarization, Bessel beams, Wavefronts, Particles, Diffraction, Beam propagation method

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Proceedings Article | 5 March 2021 Presentation

Presentation

Cascade domino lithography for extreme photon squeezing

Junsuk Rho, Inki Kim, Jungho Mun

Proceedings Volume 11696, 1169603 (2021) https://doi.org/10.1117/12.2582411

KEYWORDS: Lithography, Surface enhanced Raman spectroscopy, Raman spectroscopy, Plasmonics, Nanostructures, Nanoantennas, Gold

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Proceedings Article | 5 March 2021 Presentation

Presentation

Vectorized holographic color prints using superpixelated metasurface

Jaehyuck Jang, Inki Kim, Gyeongtae Kim, Junsuk Rho

Proceedings Volume 11694, 1169409 (2021) https://doi.org/10.1117/12.2582545

KEYWORDS: Liquid crystals, Holography, Polarization, Holograms, Modulation, Wave plates, Phase shift keying, Optical storage, Nanoantennas, Metamaterials

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Proceedings Article | 5 March 2021 Presentation

Presentation

Spectral engineering through the hybridization of Mie-scatterers and quasi-guided mode resonance: application toward gradient structural colors

Jaehyuck Jang, Trevon Badloe, Younghwan Yang, Jungho Mun, Junsuk Rho

Proceedings Volume 11695, 1169519 (2021) https://doi.org/10.1117/12.2582636

KEYWORDS: Silicon, Scattering, Mie scattering, Light scattering, Resonators, Refractive index, Waveguides, Televisions, Structural design, Solids

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Proceedings Article | 5 March 2021 Poster

Poster

On-demand design of spectrally selective multi-band absorbers using deep learning

Sunae So, Younghwan Yang, Taejun Lee, Junsuk Rho

Proceedings Volume 11703, 117031Q (2021) https://doi.org/10.1117/12.2582953

Read Abstract +

Proceedings Article | 5 March 2021 Presentation + Paper

Presentation + Paper

Chiroptical effect induced by achiral structures for full dimensional manipulation of optical waves

Hafiz Saad Khaliq, Inki Kim, Kashif Riaz, Taimoor Naeem, Muhammad Zubair, Junsuk Rho, Muhammad Qasim Mehmood

Proceedings Volume 11695, 116951M (2021) https://doi.org/10.1117/12.2579045

KEYWORDS: Mirrors, Visible radiation, Structural design, Quantum optics, Quantum information processing, Polarization, Phase shift keying, Phase modulation, Optical imaging, Nanostructures

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Proceedings Article | 22 August 2020 Poster

Poster

Anti-counterfeiting visible metaholograms multiplexed with spin, direction, and wavelengths

Inki Kim, Junsuk Rho

Proceedings Volume 11460, 114601O (2020) https://doi.org/10.1117/12.2566355

KEYWORDS: Multiplexing, Holograms, Gold, Computer generated holography, Computer programming, Titanium dioxide, Nanorods, Photonics, Wavefronts, Image quality

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Proceedings Article | 20 August 2020 Poster

Poster

Dielectric metasurface imaging platform for resolution enhancement and applicability to conventional optical system

Dasol Lee, Junsuk Rho

Proceedings Volume 11468, 114681A (2020) https://doi.org/10.1117/12.2567816

KEYWORDS: Imaging systems, Dielectrics, Resolution enhancement technologies, Image resolution, Microscopy, Laser scanners, Diffraction, Optical components, Nanolithography, Dielectric polarization

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Proceedings Article | 20 August 2020 Poster

Poster

Gradient spectral filtering using array of engineered silicon Mie-resonators

Jaehyuck Jang, Junsuk Rho

Proceedings Volume 11460, 1146024 (2020) https://doi.org/10.1117/12.2567087

KEYWORDS: Optical filters, Gallium nitride, Light scattering, Scattering, Refractive index

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Proceedings Article | 20 August 2020 Poster

Poster

A vertical hyperbolic metamaterial to enhance the optical spin Hall effect

Dasol Lee, Minkyung Kim, Junsuk Rho

Proceedings Volume 11460, 114602H (2020) https://doi.org/10.1117/12.2567831

KEYWORDS: Metamaterials, Metals, Dielectrics, Gold, Nanoimprint lithography, Control systems, Optical components, Optical filters, Sensors, Switches

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Proceedings Article | 20 August 2020 Poster

Poster

Designing photonic structures for high performance radiative cooling using genetic algorithm

Sunae So, Dasol Lee, Junsuk Rho

Proceedings Volume 11460, 114602L (2020) https://doi.org/10.1117/12.2568207

KEYWORDS: Structural design, Genetic algorithms, Photonic crystals, Raman spectroscopy, Fluctuations and noise, Reflectivity, Mid-IR, Evolutionary optimization, Solar energy, Atmospheric modeling

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Proceedings Article | 20 August 2020 Poster

Poster

Enhanced cross-polarization efficiency of a-Si:H metasurfaces via chemical equilibrium in PE-CVD

Younghwan Yang, Gwanho Yoon, Sunghak Park, Seok Nangung, Ki Tae Nam, Junsuk Rho

Proceedings Volume 11467, 114672F (2020) https://doi.org/10.1117/12.2567588

KEYWORDS: Refractive index, Modulation, Atmospheric plasma, Optical properties, Plasma, Amorphous silicon, Diffraction, Silicon

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Proceedings Article | 20 August 2020 Poster

Poster

Self-powered humidity sensor using chitosan-based plasmonic metal-hydrogel-metal filters

Jaehyuck Jang, Kyungnam Kang, Niloufar Raeis-Hosseini, Aizhan Ismukhanova, Inkyu Park, Junsuk Rho

Proceedings Volume 11461, 114612J (2020) https://doi.org/10.1117/12.2567088

KEYWORDS: Humidity, Sensors, Plasmonics, Solar cells, Resonators, Foam, Refractive index, Optical filters, Photovoltaics

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Proceedings Article | 20 August 2020 Presentation

Presentation

Extended multipole framework for describing isolated and coupled meta-atoms

Jungho Mun, Junsuk Rho, Jaehyuck Jang, Sunae So

Proceedings Volume 11462, 114621X (2020) https://doi.org/10.1117/12.2567470

KEYWORDS: Polarizability, Spherical lenses, Nanophotonics, Light scattering, Scattering, Particles, Magnetism, Plasmonics

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Proceedings Article | 20 August 2020 Presentation

Presentation

Active color filters and stimuli-responsive dynamic meta-holographic displays

Inki Kim, Junsuk Rho

Proceedings Volume 11461, 114611Y (2020) https://doi.org/10.1117/12.2566356

KEYWORDS: Optical filters, Refractive index, Solid state electronics, Ions, Nanophotonics, Liquid crystals, Optical properties, Holograms, Chemical reactions, Polarization

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Proceedings Article | 20 August 2020 Presentation

Presentation

Intelligent inverse design for nanophotonic structures using deep learning

Sunae So, Junsuk Rho

Proceedings Volume 11469, 1146914 (2020) https://doi.org/10.1117/12.2568211

KEYWORDS: Nanophotonics, Structural design, Binary data, Nanoparticles, Interfaces

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Proceedings Article | 19 August 2020 Poster

Poster

Symmetry-enforced T-matrix retrieval

Jungho Mun, Junsuk Rho

Proceedings Volume 11462, 1146225 (2020) https://doi.org/10.1117/12.2567810

KEYWORDS: Polarizability, Particles, Optical properties, Electromagnetic scattering, Scattering, Magnetism

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Proceedings Article | 19 August 2020 Poster

Poster

Sharp-NIR circular dichroism derived from twisted-layered metallic oligomers

Younghwan Yang, Minkyung Kim, Jungho Mun, Junsuk Rho

Proceedings Volume 11462, 1146231 (2020) https://doi.org/10.1117/12.2567603

KEYWORDS: Dichroic materials, Near infrared, Gold, Absorption, Electrons, Modulation, Spectroscopy, Sensors, Distribution

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Proceedings Article | 1 April 2020 Presentation + Paper

Presentation + Paper

Three-dimensional nonlinear plasmonic metamaterials

Timo Stolt, Jeonghyun Kim, Sébastien Héron, Anna Vesala, Mikko Huttunen, Robert Czaplicki, Xiaorun Zang, Martti Kauranen, Junsuk Rho, Patrice Genevet

Proceedings Volume 11345, 113451T (2020) https://doi.org/10.1117/12.2554979

KEYWORDS: Metamaterials, Second-harmonic generation, Nanoparticles, Plasmonics, Phase matching, Nonlinear optics, Nonlinear metamaterials, Silica, Signal detection

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Proceedings Article | 4 March 2019 Presentation + Paper

Presentation + Paper

Manipulating twisted light beam through all-dielectric metasurfaces

Nasir Mahmood, Muhammad Qasim Mehmood, Inki Kim, Muhammad Afnan Ansari, Tauseef Tauqeer, Farooq Ahmad Tahir, Junsuk Rho

Proceedings Volume 10928, 1092811 (2019) https://doi.org/10.1117/12.2508545

KEYWORDS: Spiral phase plates, Optical vortices, Polarization, Refractive index, Amorphous silicon, Optical components, Dielectrics, Computer simulations, Metamaterials, Wavefronts

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Proceedings Article | 7 May 2018 Paper

Paper

Micron-scale light structuring via flat nanodevices

Nasir Mahmood, Muhammad Qasim Mehmood, Inki Kim, Heongyeong Jeong, Farooq Ahmad Tahir, Junsuk Rho

Proceedings Volume 10671, 1067126 (2018) https://doi.org/10.1117/12.2314411

KEYWORDS: Dielectrics, Amorphous silicon, Spiral phase plates, Nanostructures, Metamaterials, Dielectric polarization, Optical properties, Defense technologies, Interfaces, Wavefronts

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Showing 5 of 65 publications

Conference Committee Involvement (9)

Photonic Computing: From Materials and Devices to Systems and Applications II

3 August 2025 | San Diego, California, United States

Advanced Fabrication Technologies for Micro/Nano Optics and Photonics XVIII

26 January 2025 | San Francisco, California, United States

Photonic Computing: From Materials and Devices to Systems and Applications

19 August 2024 | San Diego, California, United States

Machine Learning in Photonics

8 April 2024 | Strasbourg, France

Advanced Fabrication Technologies for Micro/Nano Optics and Photonics XVII

28 January 2024 | San Francisco, California, United States

Showing 5 of 9 Conference Committees

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