Hollow-core waveguides represent a promising type of on-chip waveguide, enabling strong light-matter interactions for guiding light directly in the medium of interest. Hollow-core waveguides are very established in fiber optics, while they receive much less attention in on-chip photonics.
Here, we will show how 3D nanoprinting is used to transfer hollow-core waveguide concepts from fiber optics to on-chip photonics. Two main types of nanoprinted waveguides are discussed, yielding a high-power fraction in the core and lateral access to the core region. We will explain applications of these waveguides in gas- and water-based spectroscopy, nanoparticle tracking analysis and optical fiber interconnection.
On-chip hollow-core waveguides represent a promising platform for microfluidic analysis, nonlinear optics and quantum information processing, due to light guidance directly inside the medium of interest. Recently, we have introduced two types of 3D nanoprinted on-chip hollow-core waveguides, namely the hollow-core light cage and the microgap waveguide which have unique properties for on-chip sensing. Here we will present our results for water-based spectroscopy, refractive index sensing, nanoparticle tracking, and optical fiber interfacing.
Wavelength-tunable femtosecond light sources are essential in various research fields and technologies, including medical diagnostics, biophotonics, and metrology. Although fiber lasers have emerged as leaders in the development of such sources, achieving wide spectral tunability for femtosecond pulses remains a significant challenge. To address this challenge, dispersive wave generation offers a powerful solution. In this study, we exploit the concept of quasi-phase matching to enable multi-order dispersive wave formation with unprecedented spectral tunability and femtosecond durations. Here, liquid-core fibers (LCFs) with periodically controlled dispersion of a higher-order mode along the fiber are applied, achieved by axial modulation of the liquid core diameter, relying on the strong dependence of dispersion on the core diameter. Nonlinear optical experiments and simulations, as well as phase-mismatching considerations based on an effective dispersion, confirm the conversion process and reveal unique emission features This resonance-empowered approach provides a versatile photonic platform with unique dispersion control capabilities for efficient, coherent femtosecond multi-frequency conversion.
We report the experimental results of ultraviolet-extended broadband supercontinuum (SC) generation in a carefully designed uniform seven-core photonic crystal fiber (PCF) pumped by Ti:sapphire femtosecond laser at 800 nm. Three different PCFs of various core diameters are fabricated to achieve group-velocity matching for ultraviolet components. A wide optical spectrum spanning down to 350 nm is obtained, which is the shortest wavelength SC generation in multicore PCF to date. High spectral flatness (10 dB) has been achieved in the entire visible window.
The visible supercontinuum (SC) sources has played an important role in biomedical applications. However, the small core size of photonic crystal fiber (PCF) restrict the development of high power SC by its small mode field area. In addition, the zero dispersion wavelength (ZDW) of the PCF with small core diameter is usually below 1 μm, which is far away from the 1.06 μm laser which is the most commonly used pump source. As the ZDW of PCF shifts away from the pump, the intensity of visible light decreases correspondingly. We promote a new technique to get an enhanced visible SC with high output power, which involves enhanced visible SC generation in a seven-core PCF pumped by a high power 1016 nm fiber laser. Muti-core PCFs offer a possibility of scaling up the mode field area to a large extent without remarkable change in dispersion properties, which show great potential in high power SC generation. Using a 1016 nm fiber laser as the pump makes the pump wavelength closer to the ZDW of PCF, which could raise the intensity of visible light. In this paper, we report an enhanced visible SC generation ranging from 400 nm to 2300 nm in a seven-core PCF pumped by a 1016 nm picosecond fiber laser. The visible light (400~800 nm) occupies 31% of the total SC power 24 W and the power of the visible light is about 7.4 W.
We design a seven-core photonic crystal fiber with specifically designed dispersion and group velocity profile which is optimized for high-power visible supercontinuum (SC) generation pumped by ∼1-μm pulsed lasers. The fiber has both a large air-filling fraction and a large effective mode field area. Additionally, the in-phase supermode of this fiber exhibits an even field distribution after mode modification. The simulation results suggest that it has a great potential to generate a high-power SC extending to 400 nm, which is highly desirable in biological applications.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.