Gongquan Liang

Stable dual-wavelength single-longitudinal-mode ring erbium-doped fiber laser for optical generation of microwave frequency

We demonstrate a simple dual-wavelength ring erbium-doped fiber laser operating in single-longitudinal-mode (SLM) at room temperature. A pair of reflection type short-period fiber Bragg gratings (FBGs), which have two different center wavelengths of 1545.072 and 1545.284 nm, are used as the wavelength-selective component of the laser. A segment of unpumped polarization maintaining erbium-doped fiber (PM-EDF) is acted as a narrow multiband filter. By turning the polarization controller (PC) to enhance the polarization hole burning (PHB), the single-wavelength and dual-wavelength laser oscillations are observed at 1545.072 and 1545.284 nm. The output power variation is less than 0.6 dB for both wavelengths over a five-minute period and the optical signal to noise ratio (OSNR) is greater than 50 dB. By beating the dual-wavelengths at a photodetector (PD), a microwave signal at 26.44 GHz is demonstrated.

Dual-wavelength Brillouin ring-cavity fiber laser with tunable channel spacing

We experimentally demonstrate a dual-wavelength Brillouin fiber laser configured a pre-amplified Brillouin pump and FBG filter in a ring-cavity. The Brillouin laser can generate 21 Brillouin Stokes with 0.084 nm spacing, the first-Stoke has a peak power of 2.19 dBm. By adjusting the TLS wavelength and FBG’s reflection wavelength from circulating in the ring-cavity, the generated output dual-wavelength is stabile and the channel spacing is tunable, the widest and narrowest channel spacing obtained is approximately 1.12 nm (139 GHz) and 0.084 nm (10.5 GHz).

An optical add-drop multiplexer design based on fiber Bragg gratings

Optical add-drop multiplexers will play an important role in enabling greater connectivity and flexibility in dense wavelength-division multiplexing (DWDM) networks. In this paper, a reconfigurable optical add-drop multiplexer (OADM) architecture using a single multiport optical circulator (MOC) and several narrow band fiber Bragg gratings (FBGs) is proposed and demonstrated. The proposed OADM exhibits a lower insertion loss and lower through loss than existing OADMs. The proposed OADM may find important applications in DWDM systems and networks.

A Novel Switchable Dual-Wavelength Ring Erbium-Doped Fiber Laser Operating in single-longitudinal-mode

In this paper, we demonstrate a simple switchable dual-wavelength ring erbium-doped fiber laser operating in single-longitudinal-mode (SLM) at room temperature. A pair of reflection type short-period fiber Bragg gratings (FBGs) is used as the wavelength-selective component of the laser. A segment of unpumped polarization maintaining erbium-doped fiber (PM-EDF) is acted as a narrow multiband filter. By turning the polarization controller (PC) to balance the gain and loss in the ring cavity, single-wavelength and dual-wavelength laser oscillations are observed. The output power variation is less than 0.6dB for both wavelengths over a five-minute period and the optical signal to noise (ONSR) is greater than 50dB.