為支援未來實驗驗證，本文亦發展一套湯姆森散射診斷系統，用於雷射產生電漿的參數定量測量。由於融合反應機率對電子密度、電子溫度與游離狀態高度依賴，實驗量測這些電漿參數對於雷射驅動核融合至關重要。本論文建立了湯姆森散射診斷系統所需的實驗光路、波長與強度校正、訊號強度估算，以及數據處理流程，並以大氣壓下奈秒雷射誘發之空氣電漿作為初步示範。;Proton-boron fusion ($p$-$^{11}\mathrm{B}$) has attracted renewed interest as a potential route toward aneutronic fusion energy due to the comparatively negligible neutrons products and uses abundant， non-radioactive fuel materials. However， in laser-driven $p$-$^{11}\mathrm{B}$ fusion schemes， the large stopping power of solid boron targets remains a major obstacle. Energetic protons lose a significant fraction of their energy before undergoing fusion reactions， which limits both the reaction probability and the overall fusion efficiency. One possible approach to mitigate this limitation is to preheat and preionize the boron target， thereby modifying the plasma stopping power experienced by incident protons.
In this thesis， the use of nanowire (NW) array targets for enhanced laser absorption and boron target heating is investigated through fully kinetic particle-in-cell (PIC) simulations. The interaction between an ultraintense laser pulse and a $^{11}\mathrm{B}$ NW array is first examined using a representative array unit-cell model， which illustrates the laser-plasma interaction mechanisms responsible for energy coupling. The dependence of laser absorptance on NW geometry is then studied to optimize target conditions. Compared with planar targets， NW array targets are shown to enhance laser absorption， electron heating， target ionization， and plasma formation. The resulting changes in electron temperature $T_e$， electron density $n_e$， and mean ionization state $\bar{Z}$ are quantified and used to evaluate their influence on proton stopping.
Using plasma parameters extracted from the PIC simulations， the electronic stopping power and fusion probability of MeV-level protons propagating through preheated boron plasma are estimated. This analysis connects the laser-target interaction physics to its potential impact on $p$-$^{11}\mathrm{B}$ fusion performance. The study is further extended to thicker target configurations in order to assess the relevance of NW-assisted heating for hot-catcher target design and future experimental optimization.
To support future experimental validation， a Thomson scattering diagnostic system is developed for quantitative characterization of laser-produced plasmas. Since proton stopping and fusion probability depend sensitively on plasma parameters ($n_e$， $T_e$， and $\bar{Z}$)， experimental access to these parameters is essential for assessing laser-preheated target schemes. The experimental layout， wavelength and intensity calibration， signal estimation， and data-processing workflow are established for collective Thomson scattering measurements and demonstrated using nanosecond-laser-induced air plasma at ambient pressure.
