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"Salah satu kajian penelitian penting dalam ranah penelitian plasmonik adalah penelitian tentang bahan yang dapat digunakan sebagai saklar pada perangkat plasmonik yang dapat dikontrol melalui mekanisme optik. Sejauh ini, beberapa penelitian telah dilakukan pada material isotropik dan disimpulkan bahwa material tersebut sebenarnya membutuhkan kerapatan daya switching yang sangat tinggi dan kemampuan switching optiknya yang sangat rendah. Baru-baru ini, studi eksperimental telah dilakukan pada bahan anisotropik SrNbO3:4 menggunakan mikroskop pump-probe dengan kerapatan daya yang sangat rendah dan ditemukan bahwa bahan ini menunjukkan penurunan reflektansi jika polarisasi medan listrik untuk mekanisme pompa berada di arah sumbu b kristal sementara Polarisasi medan listrik probe searah sumbu kristal. Menariknya lagi, kontras switching yang dihasilkan oleh material ini mencapai sekitar 90% yang dapat menjadi tanda bahwa material ini dapat digunakan sebagai plasmonic switch masa depan. Namun, penjelasan teoritis mengapa bahan ini memiliki kemampuan untuk mengubah kontras yang sangat baik belum tersedia. Dalam tesis ini, kami mencoba menjawab pertanyaan tersebut dengan menggunakan model sederhana untuk menjelaskan pengaruh bahan pada mikroskop probe pompa dan dengan menghitung prinsip utama kami menghitung nilai reflektansi sebagai fungsi waktu. Dengan memvariasikan interaksi yang diperhitungkan dalam perhitungan ini, kami menemukan bahwa ada peran penting interaksi lubang elektron dalam fenomena ini

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One of the important research studies in the realm of plasmonic research is research on material that can be used as a switch in a plasmonic device that can controlled via an optical mechanism. So far, several studies have been conducted on isotropic material and it is concluded that the material actually requires very high switching power density and its optical switching capability so low. Recently, experimental studies have been carried out on anisotropic materials SrNbO3:4 uses a pump-probe microscope with a very low power density and it was found that this material showed a decrease in reflectance if the polarization the electric field for the pump mechanism is in the direction of the b axis of the temporary crystal The polarization of the electric field of the probe is in the direction of the a-axis of the crystal. Interestingly again, The switching contrast produced by this material reaches around 90% which can be a sign that this material can be used as a future plasmonic switch. However, the theoretical explanation of why this material has the ability to switch contrast very good ones are not yet available. In this thesis, we try to answer the question using a simple model to explain the effect of material in pump-probe microscopy and by calculating our main principles calculate the reflectance value as a function of time. By varying the interaction taken into account in this calculation, we find that there is an important role of electron-hole interactions in this phenomenon."

"Penelitian ini mengeksplorasi katalisis plasmonik, berfokus pada penggunaan resonansi plasmon permukaan terlokalisasi (RPPT) dari nanopartikel untuk mendorong reaksi kimia. Berbeda dengan proses katalitik konvensional, katalisis plasmonik menawarkan sifat unik yang dapat digunakan untuk meningkatkan proses katalitik melalui peningkatan medan elektromagnetik yang diinduksi plasmon, pembentukan muatan (elektron atau hole) berenergi tinggi, atau efek fototermal. Studi numerik menunjukkan bahwa iradiasi laser pulsa dapat lebih efisien untuk katalisis yang diinduksi plasmon dibandingkan dengan laser gelombang kontinu (CW), namun investigasi eksperimental, terutama untuk sintesis nanopartikel bottom-up, masih belum banyak diselidiki. Menggunakan sintesis core-shell Au-Ag sebagai reaksi model, penelitian ini secara eksperimental menyelidiki efek eksitasi laser pulsa nanosekon. Pertama-tama, kami berhasil mensintesis nanopartikel emas (Au) berbentuk bola dengan puncak LSPR yang dapat disesuaikan mendekati panjang gelombang laser 532 nm. Percobaan pemanasan konvensional menunjukkan bahwa pembentukan core-shell terhambat secara kinetik di bawah 55°C. Laser CW (532 nm, 67 mW) tidak memiliki efek signifikan, sedangkan iradiasi laser pulsa nanosekon pada 532 nm secara signifikan menginduksi pembentukan core-shell, dibuktikan dengan pergeseran LSPR ke panjang gelombang lebih pendek yang besar dan peningkatan absorbansi. Laju pertumbuhan shell perak yang tampak meningkat seiring dengan peningkatan daya laser pulsa, menunjukkan pengaruh langsung efek plasmon terhadap kinetika pertumbuhan shell. Temuan ini memberikan pemahaman baru mengenai sintesis nanopartikel yang diinduksi laser pulsa dan potensi laser pulsa untuk meningkatkan proses katalitik secara signifikan dibandingkan metode konvensional lain.

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This study explores plasmonic catalysis, focusing on using localized surface plasmon resonance (LSPR) of nanoparticles to drive chemical reactions. In contrast to conventional catalytic processes, plasmonic catalysis offers unique properties that can be utilized to boost catalytic process via plasmonic-induced electromagnetic field enhancement, hot-carrier generation or photothermal effect. Numerical studies suggest pulsed laser irradiation can be more efficient for plasmon-induced catalysis compared to continuous-wave (CW) lasers, but experimental investigations, particularly for bottom-up nanoparticle synthesis, remain unexplored. Using Au-Ag core-shell synthesis as a model reaction, this research experimentally investigated the effect of nanosecond pulsed laser excitation. We successfully synthesized spherical Au nanoparticles with a tunable LSPR peak near the laser wavelength of 532 nm. Next, conventional heating experiments showed core-shell formation was kinetically inhibited below 55 °C. Crucially, while CW laser (532 nm, 67 mW) had little effect, nanosecond pulsed laser irradiation at 532 nm significantly induced core-shell formation, evidenced by a large LSPR blue shift and increase of absorbance. The apparent silver shell growth rate increased with increasing pulsed laser power, highlighting direct influence of plasmonic-induced effect on shell growth kinetics. These findings highlight the potential of pulsed laser to enhance catalysis significantly in comparison to other methods. "

"Applied photometry, radiometry, and measurements of optical losses reviews and analyzes physical concepts of radiation transfer, providing quantitative foundation for the means of measurements of optical losses, which affect propagation and distribution of light waves in various media and in diverse optical systems and components. The comprehensive analysis of advanced methodologies for low-loss detection is outlined in comparison with the classic photometric and radiometric observations, having a broad range of techniques examined and summarized: from interferometric and calorimetric, resonator and polarization, phase-shift and ring-down decay, wavelength and frequency modulation to pulse separation and resonant, acousto-optic and emissive - subsequently compared to direct and balancing methods for studying free-space and polarization optics, fibers and waveguides. The material is focused on applying optical methods and procedures for evaluation of transparent, reflecting, scattering, absorbing, and aggregated objects, and for determination of power and energy parameters of radiation and color properties of light."

"This book highlights the theoretical foundations of and experimental techniques in photothermal heating and applications involving nanoscale heat generation using gold nanostructures embedded in various media. The experimental techniques presented involve a combination of nanothermometers doped with rare-earth atoms, plasmonic heaters and near-field microscopy. The theoretical foundations are based on the Maxwells and heat diffusion equations. In particular, the working principle and application of AlGaN:Er3+ film, Er2O3 nanoparticles and β-NaYF4:Yb3+,Er3+ nanocrystals for nanothermometry based on Er3+ emission are discussed. The relationship between superheated liquid and bubble formation for optically excited nanostructures and the effects of the surrounding medium and solution properties on light absorption and scattering are presented. The application of Er2O3 and β-NaYF4:Yb3+,Er3+ nanocrystals to study the temperature of optically heated gold nanoparticles is also presented. In closing, the book presents a new thermal imaging technique combining near-field microscopy and Er3+ photoluminescence spectroscopy to monitor the photothermal heating and steady-state sub-diffraction local temperature of optically excited gold nanostructures."