Femtosecond laser direct writing (FLDW) of waveguides in transparent glass have found great use in photonic integration and quantum simulations. To fully take advantage of FLDW, much attention has been paid to exploring high-performance waveguides. The circular aperture, as a diffraction element in the lens focusing system, can strongly affect the intensity distribution at the focus. Here, we theoretically analyze the influence of a circular aperture on the focal volume of a collimated Gaussian beam and experimentally investigate the performance of FLDW of waveguides in a fused silica substrate with using a circular aperture. Waveguides with low propagation loss of 0.33 dB/cm, highly symmetrical mode field at 633 nm have been successfully prepared by using the circular aperture of diameter 5.5 mm. Moreover, the aspect ratio of FLDW of waveguide cross-section can be tuned by changing the diameter of the circular aperture, resulting in the manipulation of the guiding mode profile.
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.