Expand this Topic clickable element to expand a topic
Skip to content
Optica Publishing Group

Bandwidth-adjustable dynamic grating in erbium-doped fiber by synthesis of optical coherence function

Open Access Open Access

Abstract

We present an approach for bandwidth-adjustable optical filter with the dynamic grating in erbium-doped fiber (EDF). The dynamic grating is introduced by the interference of two coherent light beams counter-propagating in the pumped EDF per the phenomenon of gain saturation. The bandwidth of the grating is determined by the length of the grating, i.e., the length of the interference region. With the technique of synthesis of optical coherence function (SOCF), we localize the interference into a range at an arbitrary position along the fiber by modulating the frequency of the two interfering light beams. The length of the range is controlled by adjusting the frequency modulation parameter. In this way, the length of the dynamic grating is controlled and its reflection bandwidth then adjusted. The experimental demonstration is given.

©2005 Optical Society of America

Full Article  |  PDF Article
More Like This
Optical bit-pattern recognition by use of dynamic gratings in erbium-doped fiber

Jun Shan Wey, Douglas L. Butler, Nicholas W. Rush, Geoffrey L. Burdge, and Julius Goldhar
Opt. Lett. 22(23) 1757-1759 (1997)

Cited By

Optica participates in Crossref's Cited-By Linking service. Citing articles from Optica Publishing Group journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (5)

Fig. 1.
Fig. 1. Coherence function synthesized by sinusoidal frequency modulation.
Fig. 2.
Fig. 2. Experiment setup. VA: variable attenuator; PC: polarization controller; EDF: erbium-doped fiber; IM: intensity modulator; PD: photodiode; LIA: lock-in amplifier; FG: function generator; Ref: reference signal.
Fig. 3.
Fig. 3. Reflectivity from the dynamic grating without modulation on writing beams.
Fig. 4.
Fig. 4. Reflectivity from the dynamic grating localized by using the technique of SOCF. The length of the dynamic grating LFWHM = 75 cm.
Fig. 5.
Fig. 5. (a) Fitted reflection spectra of three different dynamic gratings, (b) normalized graphs of (a).

Equations (5)

Equations on this page are rendered with MathJax. Learn more.

r = κ sinh ( SL ) { g ˜ i ( k w k r ) } sinh ( SL ) S cosh ( SL ) ,
S 2 = κ 2 + [ g ˜ i ( k w k r ) ] 2 .
δν = c 2 πn ( π L ) 2 + κ 2 1 + ( g ˜ L π ) 2 ,
f = f 0 + f 1 cos ( 2 π f 2 t )
L FWHM [ m ] = 30 V pp [ mV ]
Select as filters


Select Topics Cancel
© Copyright 2024 | Optica Publishing Group. All rights reserved, including rights for text and data mining and training of artificial technologies or similar technologies.