| 摘要: | 本研究針對多種D–A–D結構之有機材料，系統性探討其結構設計對光學特性和自發輻射放大（ASE）行為的影響。
首先，BBTA系列兩種中心異構之D-A-D小分子材料，比較並分析其光譜、能隙與結構差異，結果顯示兩者中心異構導致發生能隙調變與發光波段紅移。
第二部分探討PT系列四種D-A-D小分子材料，其隨共軛長度增加逐漸降低閾值，然而其中2DFL-Tp-PT因加入噻吩造成扭曲與能隙變化，導致ASE閾值上升且光譜明顯紅移。
第三部分則使用D2-nPh系列（n = 2 - 5）作為主體材料，針對PT系列中ASE表現最佳之2DIndFL-PT進行摻雜，結果顯示僅D2-4Ph可成功激發客體產生ASE，推測與其優異的共軛性與分子排列有關。
此外，相較於純膜，摻雜膜展現出更低閾值，顯示主客體能量轉移有助於克服濃度焠滅與自吸收問題。綜合實驗結果，本研究釐清分子結構對ASE特性之關鍵影響，並證實主客體策略於有機固態雷射材料的可行性與潛力。
;This study systematically investigates the influence of molecular structure design on the optical properties and amplified spontaneous emission（ASE）behavior of various D–A–D type organic materials.
First, two regioisomeric D–A–D small molecules in the BBTA series, in which the central electron-accepting unit differs in linkage position, were examined to compare their spectral characteristics, energy gaps, and structural differences. The results indicate that their distinct core isomerism leads to notable modulation of energy gaps and a red-shift in emission spectra.
The second part focuses on four D–A–D compounds in the PT series. As the number of conjugated aromatic rings increases, the ASE threshold gradually decreases. However, 2DFL-Tp-PT, which incorporates a thiophene unit, exhibits increased molecular distortion and altered energy levels, resulting in a higher ASE threshold and a pronounced red-shift in emission.
In the third part, a series of D2-nPh compounds (n = 2–5) were employed as host materials to dope the best-performing PT derivative, 2DIndFL-PT. Among them, only D2-4Ph successfully triggered ASE from the guest, presumably due to its superior conjugation and favorable molecular packing.
Furthermore, compared to pristine films, doped films exhibited significantly lower ASE thresholds, demonstrating that energy transfer in host–guest systems effectively mitigates concentration quenching and self-absorption effects.
Overall, the experimental results elucidate the key structural factors affecting ASE characteristics and confirm the feasibility and potential of host–guest strategies for the development of organic solid-state laser materials. |
