Yuanfei Zhang

Southeast University (China) | SEU · School of Electronic Sicence and Engineering

We propose a compact dual-wavelength Q-switched single-frequency fiber laser based on a 17-mm-long home-made highly Er³⁺/Yb³⁺ co-doped phosphate fiber (EYDPF) and a semiconductor saturable absorber mirror (SESAM). The short cavity length and a polarization-maintaining fiber Bragg grating (PM-FBG) ensure that only one longitudinal mode is supported...

We demonstrate the generation of optical frequency combs with tunable spacing at the hundred-GHz range in the 1550-nm window. The widely spaced combs are realized through silicon-based cross-phase modulation. The optical pump is prepared by multiplication of a 10-GHz train of 1.7-ps pedestal-free pulses. Energy-efficient temporal Talbot processing...

Physical processes in the Fourier domain play a crucial role in various applications such as spectroscopy, quantum technology, ranging, radio-astronomy, and telecommunications. However, the presence of stochastic noise poses a significant challenge in the detection of broadband spectral waveforms, especially those with limited power. In this study,...

We demonstrate a multichannel entropy loading mechanism in an optical frequency comb-based coherent communication system. In high-capacity wavelength division multiplexing communications, the individual laser sources can be replaced by an optical frequency comb, thus reducing the complexity and energy consumption of the transmitter. However, the po...

We demonstrate an all-fiber optical amplifier based on parametric-assisted spectral Talbot effect to control the carrier-to-noise ratio (CNR) and the spectral spacing of optical frequency combs. The CNR is enhanced by up to 11 dB while the spacing is multiplied from 11 to 165 GHz.

Optical frequency combs (OFCs) with programmable free spectral range and high optical carrier-to-noise ratio (CNR) play a crucial role in diverse research fields, including telecommunications, spectroscopy, quantum information, astronomy, sensing, and imaging. Unfortunately, the presence of stochastic noise often results in degraded optical CNR, le...

An optical frequency comb with multiplied mode spacing of 94.5 GHz and up to 35 dB carrier-to-noise ratio is produced by a hybridly amplified spectral Talbot processor. The output supports frequency comb based coherent communications.

We propose and demonstrate a novel scheme to flexibly generate optical pulse trains with programmable repetition rates using newly designed binary modulation coefficients. The required coefficients are devised based on the principle of real-time Fourier transform (RTFT). By applying binary modulation with a Mach-Zehnder intensity modulator on a per...

Using cross-phase modulation based spectral Talbot amplifier, we achieve purification and in-band noise mitigation of arbitrary broadband spectral waveforms. The optical signal-to-noise-ratio is improved by 9 dB, enabling recovery of spectral waveforms hidden under noise.

Using temporal Talbot processing followed by cross-phase modulation in a silicon-on-insulator waveguide, we experimentally multiply the repetition rate of a 10-GHz optical pulse train and generate widely spaced optical frequency combs up to 50 GHz.

Phase manipulation is crucial for radio frequency (RF) and optical signal processing. In this work, we introduce an interferometric phase-reduction scheme to flexibly suppress the phase change while simultaneously amplifying the signal. We develop a numerical model to evaluate the characteristics of this processing scheme. The concept is further de...

Using a silicon-based four-wave mixing interferometer, we apply phase-amplification to magnify the optical delay induced by stimulated Brillouin scattering slow light. The delay can be effectively tuned by controlling the power of a reference pulse.

Using modulation-assisted temporal Talbot processing followed by cross-phase modulation in a silicon-on-insulator (SOI) waveguide, we multiply the repetition rate of a 10-GHz optical pulse train and generate widely spaced optical frequency combs with programmable spacing.

We controlled the phase matching for four-wave mixing (FWM) in a chalcogenide waveguide by Brillouin-induced phase shift. Over 2n phase shift was realized and a 6-dB improvement in FWM conversion efficiency was obtained.

We investigated the frequency noise in the distributed Bragg reflector single-frequency fiber laser (DBR-SFFL) theoretically and experimentally. A complete theoretical analysis is demonstrated by considering the energy-transfer upconversion (ETU) process and establishing linkages between the frequency noise and the relative intensity noise (RIN) of...

We present a compact passively Q-switched single-frequency fiber laser based on a 12-mm-long laboratory-built highly Er³⁺/Yb³⁺ codoped phosphate fiber (EYDPF) and a semiconductor saturable absorber mirror (SESAM). An effective cavity length of less than 20 mm ensures the stable single-frequency operation of the Q-switched fiber laser. By employing...

An efficient low-noise, single-frequency 1033 nm master oscillator power amplifier (MOPA) Yb³⁺-doped phosphate fiber (YPF) laser system is demonstrated. A maximal output power of 612 mW with a laser linewidth of <1.2 kHz is obtained from a 3.7 cm long YPF. By suppressing the intensity noise of the short-cavity phosphate fiber oscillator with a semi...

Based on a self-injection locking scheme and the nonlinear amplification effect of a semiconductor optical amplifier, a low intensity noise amplified ultrashort cavity single-frequency fiber laser at 978 nm is demonstrated with a final output power of > 230 mW and a broad temperature range of > 15 °C for single-longitudinal-mode operation. The effe...

An ultra-narrow linewidth full C-band tunable single-frequency linear-polarization fiber laser based on self-injection locking has been demonstrated. By the use of a tunable narrow-band fiber Fabry-Perot interferometer, the laser wavelength could be flexibly tuned from 1527 to 1563 nm with linewidths of < 700 Hz. The laser frequency noise is less t...

Based on heavily Tm-doped germanate glass fibers (TGFs), a short all-TGF MOPA laser system with uniform core parameters in each stage was demonstrated. An 11.7 W stable single-frequency laser at 1.95 μm with an optical-to-optical conversion efficiency of 20.4% is obtained from a homemade 31-cm-long double-cladding single-mode TGF. The estimated sti...

An all-fiber Yb-doped kHz-linewidth low-noise linearly polarized single-frequency master-oscillator power-amplifier (MOPA) laser with a stable CW output power of >52 W is demonstrated. By suppressing the intensity noise of the DBR phosphate fiber oscillator, the linewidth of MOPA laser is not noticeably broadened, and an ultra-narrow linewidth of <...

Based on a temperature-dependent longitudinal-mode-selection model, a broad temperature range for single-longitudinal-mode (SLM) operation of a short DBR phosphate fiber laser has been demonstrated. In order to make the variety in cavity resonance wavelength match the reflection peak changing in fiber Bragg grating (FBG) when the ambient temperatur...

A linearly frequency-modulated, actively Q-switched, single-frequency ring fiber laser based on injection seeding from an ultra-short cavity is demonstrated at 1083 nm. A piezoelectric transducer is employed to obtain linearly frequency-modulating performance and over 1.05 GHz frequency-tuning range is achieved with a modulating frequency reaching...

A compact frequency-modulation Q-switched single-frequency fiber laser is demonstrated at 1083 nm. The short linear resonant cavity consists of a 12 mm long homemade Yb 3+-doped phosphate fiber and a pair of fiber Bragg gratings (FBGs) in which the Q-switching and the frequency excursion is achieved by a tensile-induced period modulation. Over 375...

A compact frequency-modulation Q-switched single-frequency fiber laser has been demonstrated at 1.0 μm utilizing a piezoelectric transducer. Hundreds-of-megahertz frequency-tuning range is achieved and the highest peak power of the pulse reaches almost 7.0 W.