Study of strain-engineered photoluminescence and nonlinear properties in SnP2S6 thin films
- 주제(키워드) strain-engineering , photoluminescence , nonlinear optics , SnP₂S₆ , wrinkle
- 주제(DDC) 621.042
- 발행기관 아주대학교 일반대학원
- 지도교수 Dong-Il Yeom
- 발행년도 2026
- 학위수여년월 2026. 2
- 학위명 석사
- 학과 및 전공 일반대학원 에너지시스템학과
- 실제URI http://www.dcollection.net/handler/ajou/000000035932
- 본문언어 영어
- 저작권 아주대학교 논문은 저작권에 의해 보호받습니다.
초록/요약
Two-dimensional ferroelectric materials are promising platforms for strain-tunable optoelectronic and nonlinear optical devices due to the strong coupling between lattice distortion, electronic structu re, and optical response. In this thesis, we systematically investigate strain-engineered optical and n onlinear optical properties of exfoliated SnP₂S₆ thin films by introducing controlled strain morpholo gies, including periodic wrinkles, microbubbles, and standing wrinkles, using flexible substrates an d optimized spin-coating encapsulation to ensure structural stability. Photoluminescence measureme nts reveal pronounced strain-induced modulation, with ~3-4 times enhancement at periodic wrinkle crests and ~4-fold enhancement with a redshift in standing wrinkles, indicating localized bandgap m odification. Nonlinear optical measurements further show significant harmonic enhancement, reachi ng ~8-fold in bubble-induced strain regions. These results establish a direct correlation between eng ineered strain morphologies and enhanced linear and nonlinear optical responses in SnP₂S₆, highligh ting its potential for flexible, strain-tunable photonic and nonlinear optoelectronic applications. Keywords strain-engineering, photoluminescence, nonlinear optics, SnP₂S₆, wrinkle
more목차
1. Introduction 1
2. Literature review 2
2.1 Photoluminescence 2
2.2 Nonlinear Optics 3
2.2.1 Nonlinear polarization 3
2.2.2 Nonlinear optical interactions 6
2.3 Transition-meta thiophosphate 8
2.3.1 Tin Thiophosphate SnP2S6 9
2.4 Strain-engineering in two-dimensional semiconductors 12
2.4.1 Strain-engineering methods 13
2.4.2 Strain-dependent optical modulation 17
3. Experimental Methodology 21
3.1 Uniaxial strain application setup 21
3.1.1 Uniaxial stretching configuration 21
3.1.2 Uniaxial bending configuration 22
3.2 Strain Induces structural artifacts 22
3.2.1 Bubbles and Blisters 23
3.2.2 Periodic wrinkles 24
3.2.3 Standing wrinkles 26
3.3 Nonlinear optical microscopy 27
4. Experimental results and discussion 30
4.1 Material Characterization 30
4.2 Structural comparison of strain artifacts 33
4.3 Strain-engineered Photoluminescence 36
4.4 Starin-engineered nonlinear optical signals 39
5. Conclusion 43
Bibliography 44
