Abstract

A simple system of linearly tunable fiber–film wavelength-dependent components is demonstrated that includes a linearly tapered high-index thin-film planar waveguide (PWG) evanescently coupled by a single-mode-fiber half-coupler. We present experimental and theoretical results for the linear tuning of spectral responses such as coupled power, resonance position (λ0), and fiber output-light polarization through position shifting of the linearly tapered PWG, in the direction of the propagating light in the fiber, over the half-coupler block. We achieved almost linear control of the spectral response by changing the temperature of mixture-of-oils and overlay-doped poly(methyl methacrylate) PWG’s when the refractive index of the system decreases with temperature. The variation in thickness of the tapered film is along the direction of the interaction length of the system. Linear tapered PWG’s that comprised a mixture of oils, BK7 glass, and overlay-doped PMMA with high refractive indices were fabricated that could operate the device at lower and higher modes. We investigated the dependence of tuning λ0 on the PWG mode. Tuning by shifting of a linear tapered PWG over a fiber half-block is mode dependent, whereas tuning by changing the refractive index of a uniform PWG is mode independent. Wavelength shift Δλ0 is found to decrease with an increase in the resonant PWG mode number m for linearly tapered PWG’s. A fiber-to-asymmetric linear tapered–PWG coupler, which maintains the taper slope to within a specific limit, can function as a linearly tunable polarizer for the light in the fiber.

© 1999 Optical Society of America

Full Article  |  PDF Article
OSA Recommended Articles
Single-mode fiber–linearly tapered planar waveguide tunable coupler

Alok K. Das and Anwar Hussain
Appl. Opt. 36(27) 6822-6827 (1997)

Evanescent field coupling between a single-mode fiber and a planar waveguide with absorption or gain

Krassimir P. Panajotov
J. Opt. Soc. Am. B 13(11) 2468-2476 (1996)

References

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Figures (5)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Tables (1)

You do not have subscription access to this journal. Article tables are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Equations (11)

You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Metrics

You do not have subscription access to this journal. Article level metrics are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription