First demonstration of a 12 DFB fiber laser array on a 100 GHz ITU grid, for underwater acoustic sensing application

Abstract

We report for the first time a multiplexed array of 12 distributed feedback fiber lasers (DFB FLs) on a single optical fiber, separated by only 100 GHz (0.8 nm) in the C-band. These lasers are pumped by a 200 mW laser diode at 1480 nm with no apparent impact on the sensor noise floor despite the fact that the residual reflections from adjacent gratings may be enhanced due to the smaller wavelength separation. Each DFB FL, especially developed for serial multiplexing, exhibits low lasing threshold typically between 1 and 2 mW, low intensity noise and very low frequency noise (less than 30 dB re 1 Hz 2 /Hz at 1 kHz from optical carrier). From these experimental results, extension to 32 DFB FLs array (on 100 GHz ITU grid) multiplexed on one fiber will be discussed.

Multi-wavelength narrow linewidth fiber laser based on distributed feedback fiber lasers

“…For RIN test, the optical fiber interferometer in the soundproof box is removed, and the laser is directly incident to the photodetector (PD). The real algorithm is according to the definition of RIN in the corresponding optical testing handbook and referenced publications [9]. RIN is the ratio of the mean-square optical intensity noise to square of the average optical power: The linewidth is measured by using the delayed self-homodyne method with a 55-km optical fiber delay line.…”

“…In recent years, the narrow linewidth fiber laser with the compact structure has been realized in distributed feedback fiber laser (DFB-FL) where a short phase shifted fiber grating in erbium doped fiber as the distributed feedback laser cavity assures the robust single longitudinal mode operation [4][5][6][7]. This distributed feedback fiber laser can be used as a sensing element in the high sensitive acoustic detecting field and has been extensively studied previously [8,9]. Meanwhile, it can be used as a seed laser of the high performance laser source for its excellent single frequency narrow linewidth characteristic and simple structure [10].…”

Fiber laser design and measurements for fiber optical hydrophones in their application for ultra-high energy neutrino detecti

“…Although multiplexing of fiber lasers has been achieved before, see e.g. [12], we investigate here the limits that are introduced by a really short fiber laser design. In figure 5 we draw the schematics of a number of hydrophones that are serially multiplexed on a single fiber.…”

Wireless, Portable Fiber Bragg Grating Interrogation System Employing Optical Edge Filter

“…This method has the advantage of being able to measure many FBGs simultaneously because it has an intrinsic wavelength division multiplexing (WDM) scheme. The (2) interferometer-type interrogators employ a kind of interferometer, such as q Mach–Zehnder [8,35] or Michelson interferometer [36]. This has the great potential for measuring Bragg wavelength with extremely high precision [8,36].…”

“…The (2) interferometer-type interrogators employ a kind of interferometer, such as q Mach–Zehnder [8,35] or Michelson interferometer [36]. This has the great potential for measuring Bragg wavelength with extremely high precision [8,36]. These two methods have already been used in commercially available FBG interrogators.…”