Media 1: Real-time observation of birefringence by laser-scanning surface plasmon resonance microscope

Originally published in Optics Express on 05 September 2005 (oe-13-18-6905

Computational Simulation of CO₂/CH₄ Separation on a Three-Dimensional Cd-Based Metal–Organic Framework

Natural gas purification and biogas recovery require efficient separation of CO2 from CH4, as CH4 is increasingly being recognized as a promising substitute for petroleum due to its environmentally sustainable nature, abundance in natural resources, and economic benefits. In the present work, a 3D Cd-based metal–organic framework, [Cd2(DBrTPA)2(DMF)3] (MUT-11) 2,5-[dibromoterephthalic acid (DBrTPA) and dimethyl formamide (DMF)] was synthesized using a combination of different synthetic methods and fully characterized via several techniques. Additionally, a variety of organic solvents were employed to perform the solvent stability test. The MUT-11 structure was subjected to Grand Canonical Monte Carlo and molecular dynamics simulations to study the adsorption characteristics of CO2 and CH4 gases in both pure and binary states. The results acquired through the simulation-based analysis revealed that the adsorption of CO2 is dominant in all pressure and temperature conditions

Three-dimensional coherent transfer function for reflection confocal microscopy in the presence of refractive-index mismatch

The three-dimensional (3-D) coherent transfer function for reflection confocal microscopy of high-numerical-aperture objectives is derived and calculated in the presence of refractive-index mismatch when a laser beam is focused into a medium of refractive index different from its immersion medium. This aberrated coherent transfer function is then used to estimate the readout efficiency of 3-D data bits recorded in a thick medium. It is shown that the readout efficiency of confocal microscopy for 3-D bit data storage is decreased with the focal depth of an objective in a recording medium. However, a high readout efficiency can be maintained if the tube length of a reading objective is linearly altered to compensate for the spherical aberration caused by the refractive-index mismatch

Dynamic SERS Imaging of Cellular Transport Pathways with Endocytosed Gold Nanoparticles

Dynamic SERS imaging inside a living cell is demonstrated with the use of a gold nanoparticle, which travels through the intracellular space to probe local molecular information over time. Simultaneous tracking of particle motion and SERS spectroscopy allows us to detect intracellular molecules at 65 nm spatial resolution and 50 ms temporal resolution, providing molecular maps of organelle transport and lisosomal accumulation. Multiplex spectral and trajectory imaging will enable imaging of specific dynamic biological functions such as membrane protein diffusion, nuclear entry, and rearrangement of cellular cytoskeleton

Multiphoton-excited DUV photolithography for 3D nanofabrication

Light-matter interactions in the deep ultraviolet (DUV) wavelength region exhibits a variety of optical effects such as luminescence, photoisomerization, and polymerization in many materials. Despite the rich photochemistry and high spatial resolution due to the short wavelength, the notorious lack of DUV-compatible optical components and devices precludes use of DUV light in microscopy and lithography as a routine laboratory tool. Here, we present the use of two-photon excitation with visible laser light to realizes photo-polymerization of molecules with an excitation energy equivalent to DUV light. Using standard optics for visible light, methacrylate oligomers were polymerized with 400 nm femtosecond pulses without any addition of photo-initiators and sensitizers. By scanning the laser focus in 3D, a series of fine 3D structures were created with the smallest resolved line-space features of 80 nm. We found DUV polymerizations induced by two-photon absorption is surprisingly efficient and requires laser intensity only on the order of 100 kW/cm^2. With the variety of successful demonstrations including organic- and inorganic-material-made-structures presented, our direct nano-3D-printing method would be a valuable tool for nanofabrication in 3D

Media 4: Multi-focus excitation coherent anti-Stokes Raman scattering (CARS) microscopy and its applications for real-time imaging

Originally published in Optics Express on 08 June 2009 (oe-17-12-9526

Dynamic SERS Imaging of Cellular Transport Pathways with Endocytosed Gold Nanoparticles

Dynamic SERS imaging inside a living cell is demonstrated with the use of a gold nanoparticle, which travels through the intracellular space to probe local molecular information over time. Simultaneous tracking of particle motion and SERS spectroscopy allows us to detect intracellular molecules at 65 nm spatial resolution and 50 ms temporal resolution, providing molecular maps of organelle transport and lisosomal accumulation. Multiplex spectral and trajectory imaging will enable imaging of specific dynamic biological functions such as membrane protein diffusion, nuclear entry, and rearrangement of cellular cytoskeleton

Media 1: Multi-focus excitation coherent anti-Stokes Raman scattering (CARS) microscopy and its applications for real-time imaging

Originally published in Optics Express on 08 June 2009 (oe-17-12-9526

Media 2: Multi-focus excitation coherent anti-Stokes Raman scattering (CARS) microscopy and its applications for real-time imaging

Originally published in Optics Express on 08 June 2009 (oe-17-12-9526