Frequency-shifted Feedback Fiber Laser Research Articles

Study of a mode-locked erbium-doped frequency-shifted-feedback fiber laser incorporating a broad bandpass filter: Experimental results

We present rigorous experimental studies on the spectral and temporal behaviors of an erbium-doped frequency-shifted-feedback fiber laser (FSFL), with respect to various parameters of the laser cavity, including the direction of the frequency-shift mechanism, the quantity of frequency-shift, and the output coupling ratio (OCR) of the cavity. We show that if the filter bandwidth is much broader than the laser linewidth, the laser spectrum tends to split and form a secondary spectral band (SSB) on the shorter or longer wavelength side of the primary spectrum, depending on whether the direction of the frequency-shift mechanism is upward or downward, respectively. We found that the SSB forms a parasitic pulse with much lower peak power traveling on the leading or trailing edge of the primary pulse, which leads to a significant asymmetry in the whole pulse formation in the time domain.

Controlling the frequency of the frequency-shifted feedback fiber laser using injection-seeding technique

In this paper we describe the stabilization of the optical frequency comb (OFC) generated by the frequency-shifted feedback (FSF) erbium fiber laser. Frequency of the comb is controlled using the distributed feedback laser diode seeded into the cavity of the FSF laser. When the DFB diode is stabilized to the molecular absorption line of hydrogen cyanide frequency stabilized OFC is obtained.

Frequency-Shifted Feedback Fiber Laser Oscillation with Monolithically Integrated Tandem Waveguide-Type Acoustooptic Modulator Driven by Surface Acoustic Waves

Frequency-shifted feedback fiber laser oscillation and optical frequency domain ranging using a monolithically integrated tandem acoustooptic modulator driven by surface acoustic waves (SAWs) were demonstrated. The linear relationships between the beat frequency change and the optical path difference in the Mach–Zehnder interferometer with three slopes were obtained by combining the upward and downward frequency shifts in the first and second SAWs.

High power and high energy ultrashort pulse generation with a frequency shifted feedback fiber laser

The highest average power that has been achieved with a frequency-shifted feedback modelocked fiber laser is reported. Subpicosecond pulses with 40 kW peak power are obtained by this technique for the first time by using external pulse compression. The pulsing is self starting and environmentally stable. The measured pulse energy in modelocked operation is 120 nJ. The pulses could be compressed to 855 fs. The pulse energy was increased to 1muJ with controlled Q-switched modelocking.

2-04P-23 Frequency-Shifted Feedback Fiber Laser Oscillation with Monolithically Integrated Tandem Waveguide-Type AOM Driven by SAWs(Poster session 2)

2-04P-23 Frequency-Shifted Feedback Fiber Laser Oscillation with Monolithically Integrated Tandem Waveguide-Type AOM Driven by SAWs(Poster session 2)

Tunable Picosecond Frequency-Shifted Feedback Fiber Laser at 1550 nm

A novel frequency-shifted feedback (FSF) fiber laser cavity is proposed and experimentally verified. The laser generates stable mode-locked pulses of <2 ps, mainly limited due to chirp induced by the frequency-shifting element (i.e., the acoustooptic modulator) on the pulses. Fourier transform-limited subpicosecond pulses were obtained by compensating this excess chirp using a piece of single-mode fiber SMF-28 outside the laser cavity. The unique cavity design also allow us to tune the pulse wavelength throughout the Er-gain band and the ability of the laser to self-start gives us the opportunity to characterize transient behavior of mode-locked pulses in an FSF fiber laser cavity.

P2-E-48 Waveguide-Type Acousto-Optic Frequency Shifter driven by SAW and its Application to Frequency-Shifted Feedback Fiber Laser

P2-E-48 Waveguide-Type Acousto-Optic Frequency Shifter driven by SAW and its Application to Frequency-Shifted Feedback Fiber Laser

Novel PMD measurement method based on OFDR using a frequency-shifted feedback fiber laser

We propose a new method to measure polarization mode dispersion (PMD) in optical fibers based on optical frequency domain reflectometry technique. In this method the PMD is directly determined from the beat frequency generated by interference between lights from the Fresnel reflection at the end of the device under test, which makes the measurement at single end of the device possible. An automated PMD measurement system is demonstrated on polarization maintaining fibers with a frequency-shifted feedback fiber laser as a light source.

A new method for measurement of group velocity dispersion of optical fibers by using a frequency-shifted feedback fiber laser

A new method for the measurement of the group velocity dispersion (GVD) in optical fibers, based on optical frequency domain reflectometry (OFDR), is proposed and demonstrated. Frequency chirped light is used as a light source, which allows the dispersion to be determined from changes in the frequency chirp rate. Accurate measurement of the average dispersion, at a single terminal, in fibers up to several tens of kilometers, is accomplished using a frequency-shifted feedback fiber laser as a light source.

Frequency-Shifted Feedback Fiber Laser.

In the frequency-shifted feedback laser (FSF laser), a frequency shift is imposed on an intracavity light field by feedback of the first order diffracted light of an acousto-optic modulator (AOM). Here we report the first observation of a chirped frequency comb output from this type of laser with erbium-doped fiberas a gain medium, and investigate its application to optical reflectometry. The spatial resolution is demonstrated to be 1.5 mm.