Advanced mid-infrared optical parametric sources: from fundamentals to applications
File(s)
Author(s)
Temel, Tugba
Type
Thesis
Abstract
The mid-infrared (mid-IR) spectral region is crucial for numerous applications due to its alignment with molecular absorption lines. This research explores the development of three distinct parametric sources using nonlinear down-conversion techniques and investigates their applications in this spectral range. The study begins with a non-resonant optical parametric oscillator (NRO) de-signed to generate narrow-band, nanosecond pulses at 2.3 μm with kHz repetition rates. This source serves as the foundation for a cascaded scheme extending beyond 5 μm. Experimental and simulation-based analyses highlight the NRO’s potential for long-wavelength generation.
The second focus is the development of a femtosecond, tunable optical parametric amplifier (OPA) centered at 3.2 μm, delivering microjoule-level pulse energies. This source enables the investigation of nonlinear optical responses in two-dimensional materials, providing insights for next-generation mid-IR photonic and optoelectronic devices. Specifically, the nonlinear properties of two-dimensional layered γ-InSe are explored using this OPA, where multiphoton harmonic generation is observed. To further enhance its nonlinear response, γ-InSeis integrated with a plasmonic metasurface, demonstrating an enhancement in nonlinear optical effects. These findings highlight the potential of γ -InSe for future applications in nonlinear optics.
The final focus of this thesis is the investigation of laser-tissue interactions. For this purpose, a high-energy, 100 Hz, picosecond OPA source centered at 2.94 μm is developed, specifically designed for laser ablation of biological tissue. This study includes preliminary results on tissue ablation tracks at different repetition rates.
Finally, these three distinct projects are unified under the theme of mid-IR source development and its applications, demonstrating the versatility and significance of parametric sources. Our results contribute to ongoing research in the field.
The second focus is the development of a femtosecond, tunable optical parametric amplifier (OPA) centered at 3.2 μm, delivering microjoule-level pulse energies. This source enables the investigation of nonlinear optical responses in two-dimensional materials, providing insights for next-generation mid-IR photonic and optoelectronic devices. Specifically, the nonlinear properties of two-dimensional layered γ-InSe are explored using this OPA, where multiphoton harmonic generation is observed. To further enhance its nonlinear response, γ-InSeis integrated with a plasmonic metasurface, demonstrating an enhancement in nonlinear optical effects. These findings highlight the potential of γ -InSe for future applications in nonlinear optics.
The final focus of this thesis is the investigation of laser-tissue interactions. For this purpose, a high-energy, 100 Hz, picosecond OPA source centered at 2.94 μm is developed, specifically designed for laser ablation of biological tissue. This study includes preliminary results on tissue ablation tracks at different repetition rates.
Finally, these three distinct projects are unified under the theme of mid-IR source development and its applications, demonstrating the versatility and significance of parametric sources. Our results contribute to ongoing research in the field.
Version
Open Access
Date Issued
2025-02-25
Date Awarded
01/10/2025
License URL
Advisor
Murray, Robert
Publisher Department
Department of Physics
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)