Femtosecond laser inscription of Bragg gratings in Tm-doped fluorotellurite glass fibers for lasing at 2.3 µm.

In this paper, fiber Bragg gratings (FBGs) are inscribed in Tm-doped fluorotellurite glass fiber (TDFTF) and applied to construction of a 2.3-µm all-fiber laser. The FBGs with a center wavelength of 2.

Monolithic integration of waveguide amplifiers and passive polymer photonic devices using photolithography.

The monolithic integration of rare-earth-doped waveguide amplifiers with passive photonic devices has long been a subject of extensive research. Herein, we propose a method for active-passive monolithic integration based on polymer photonic integrated devices. The monolithic integration of passive devices with active waveguide amplifiers is achieved by spin-coating an active layer atop a passive polymer waveguide and subjecting specific regions of the active layer to selective photolithography.

Voltage-controlled nonlinear optical properties in gold nanofilms via electrothermal effect.

Dynamic control of the optical properties of gold nanostructures is crucial for advancing photonics technologies spanning optical signal processing, on-chip light sources and optical computing. Despite recent advances in tunable plasmons in gold nanostructures, most studies are limited to the linear or static regime, leaving the dynamic manipulation of nonlinear optical properties unexplored. This study demonstrates the voltage-controlled Kerr nonlinear optical response of gold nanofilms via the electrothermal effect.

Widely tunable S-band ring-cavity Tm-doped fluorotellurite fiber laser.

Tm-doped fluorotellurite fibers (TDFTFs) are fabricated by using a rod-in-tube method. A 2.1 m long TDFTF is used as the gain medium, in which both ends of the TDFTF are connected to a short piece of a silica fiber by direct fusion splicing.

Intense emission at 605 nm from Pr-doped fluorotellurite glass fibers.

Pr-doped fluorotellurite glass fibers (PDFTFs) were fabricated by using a rod-in-tube method. By using a 976/1400 nm dual-wavelength upconversion pump technique, an intense emission at 605 nm was obtained from a 6 cm long PDFTF, which was attributed to the transition D→ H of Pr ions. With an increase in power of the 1400 nm laser from ∼34 to ∼136 mW, the spectral bandwidth of the 605 nm emission decreased and the intensity of the 605 nm emission increased monotonically, indicating the generation of 605 nm amplified spontaneous emission (ASE).

Strip loaded waveguide amplifiers based on erbium-doped nanocomposites with 17 dB internal net gain.

We propose a strip loaded amplifier employing SU-8 as the loaded waveguide and nanoparticles (NPs)-polymethyl methacrylate (PMMA) as the cladding layer. By leveraging the undoped SU-8 loaded waveguide, the polymer waveguide amplifier accomplished remarkably low transmission losses, reaching as low as 1.8 dB/cm at 1530 nm.

Bidirectional mode-locked erbium-doped fiber laser based on an all-fiber gold nanofilm saturable absorber.

We demonstrate a bidirectional mode-locked erbium-doped fiber laser by incorporating gold nanofilm as a saturable absorber (SA). The gold nanofilm SA has the advantages of high stability and high optical damage threshold. Besides, the SA exhibits a large modulation depth of 26% and a low saturation intensity of 1.

Boosting the Downconversion Luminescence of Tm-Doped Nanoparticles for S-Band Polymer Waveguide Amplifier.

Polymer waveguide devices have attracted increasing interest in several rapidly developing areas of broadband communications since they are easily adaptable to on-chip integration and promise low propagation losses. As a key member of the waveguide gain medium, lanthanide doped nanoparticles have been intensively studied to improve the downconversion luminescence. However, current research efforts are almost confined to erbium-doped nanoparticles and amplifiers operating at the C-band; boosting the downconversion luminescence of Tm for S-band optical amplification still remains a challenge.

Watt-level 815 nm lasing from Tm-doped fluorotellurite glass fibers.

Tm-doped fluorotellurite fibers based on TeO-BaF-YO(TBY) glasses were fabricated by using a rod-in-tube method. By using an 81 cm-long Tm-doped fluorotellurite fiber as the gain medium and a 1400 / 1570 nm dual-wavelength pump technique, lasing at 815 nm was obtained for a threshold pump power of 629 mW at 1400 nm and a fixed pump power of 960 mW at 1570 nm. As the 1400 nm pump power is increased to 1803 mW, the obtained maximum output power was about 1616 mW.

Over 50 W all-fiber mid-infrared supercontinuum laser.

Broadband supercontinuum laser sources in the mid-infrared region have attracted enormous interest and found significant applications in spectroscopy, imaging, sensing, defense, and security. Despite recent advances in mid-infrared supercontinuum laser sources using infrared fibers, the average power of those laser sources is limited to 10-watt-level, and further power scaling to over 50 W (or hundred-watt-level) remains a significant technological challenge. Here, we report an over 50 W all-fiber mid-infrared supercontinuum laser source with a spectral range from 1220 to 3740 nm, by using low loss (<0.

Gain enhancement technique for S-band polymer-based waveguide amplifiers.

The S-band polymer-based waveguide amplifier has been fabricated, but how to improve the gain performance remains a big challenge. Here, using the technique of establishing the energy transfer between different ions, we successfully improved the efficiency of Tm:F→H and H→F transitions, resulting in the emission enhancement at 1480 nm and gain improvement in S-band. By doping the NaYF:Tm,Yb,Ce@NaYF nanoparticles into the core layer, the polymer-based waveguide amplifier provided a maximum gain of 12.

(S + C)-band polymer waveguide amplifier based on Tm and Er layer-doped core-shell nanoparticles.

Optical waveguide amplifiers are essential devices in integrated optical systems. Their gain bandwidths directly determine the operating wavelength of optical circuits. Due to the difficulty of developing wideband gain media, it has been a challenge to fabricate devices with broadband amplification capability, resulting in few reports on multi-band polymer waveguide amplifiers.

Thulium-doped fluorotellurite glass fibers for broadband S-band amplifiers.

We demonstrated broadband S-band (1460-1530 nm) amplification in Tm-doped fluorotellurite glass fibers (TDFTFs) by using a 1400/1570 nm dual-wavelength pump technique. TDFTFs based on TeO-BaF-YO (TBY) glass were fabricated by using a rod-in-tube method. For an input signal power of 0 dBm (or 1 mW), a broadband positive net gain ranging from <1440 nm to 1546 nm was achieved in a 1.

Third-order cascaded Raman shift in all-solid fluorotellurite fiber pumped at 1550 nm.

In this Letter, we demonstrate a third-order cascaded Raman shift in an all-solid fluorotellurite fiber pumped by a 1550 nm nanosecond laser. The fluorotellurite glass with a composition of TeO-BaF-YO (TBY) has a usable Raman shift of ∼785 cm and a Raman gain coefficient of ∼1.65 × 10 m/W at 1550 nm, which is approximately 25.

Polymer-based S-band waveguide amplifier using NaYF:Yb,Tm-PMMA nanocomposite as gain medium.

Optical waveguide amplifiers are essential to improve the performance of integrated communication systems. Previous research has mainly focused on C- and L-bands amplification, but there are few reports on S-band waveguide amplifiers. Here, we introduce a polymer-based waveguide amplifier that uses a NaYF:Yb,Tm nanoparticles-PMMA nanocomposite as gain medium, which can provide loss compensation in the S-band.

Efficient ∼4 µm emission from Pr/Yb co-doped fluoroindate glass.

/ co-doped fluoroindate () glasses were prepared by using a traditional melt-quenching method in dry atmosphere. Pumped by a 976 or 1570 nm laser diode, efficient emissions at ∼4µ were obtained from the / co-doped glasses, which could be ascribed to the transition → of ions. The relative stimulated emission cross section was calculated to be ∼1.

Unlocking the ultrafast potential of gold nanowires for mode-locking in the mid-infrared region.

In this Letter, we present the mode-locking operation of a 2.87 µm / codoped fluoride fiber laser, helped by the ultrafast nonlinear optical absorption behavior of gold nanowires (GNWs). The mode locker is fabricated by depositing the GNW solution onto a silver mirror.

Intense emission at ∼3.3 µm from Er-doped fluoroindate glass fiber.

Fluoroindate glass fibers with an doping concentration of ∼0.5 were fabricated by using a rod-in-tube method. Pumped by a 976 nm laser diode, intense emission at ∼3.

Passively Mode-Locked Operations Induced by Semiconducting Polymer Nanoparticles and a Side-Polished Fiber.

Semiconducting polymer nanoparticles (SPNs) possess many special photophysical and chemical properties. However, little research has been done on the potential of SPNs in laser technology. In this work, we present the ultrafast pulses generation at 1.

Linearly polarized single-frequency fiber laser based on the Yb:YAG-crystal derived silica fiber.

A linearly polarized low-noise single-frequency fiber laser was demonstrated by using a homemade 1.2-cm-long Yb:YAG crystal derived silica fiber. A maximum output power of greater than 60 mW was obtained with a signal-to-noise ratio of ∼80 and a polarization extinction ratio of 27.

22.7 W mid-infrared supercontinuum generation in fluorotellurite fibers.

In this Letter, we demonstrate 22.7 W mid-infrared (MIR) supercontinuum (SC) generation in all-solid fluorotellurite fibers. All-solid fluorotellurite fibers based on ${{\rm TeO}_2} {\text -} {{\rm BaF}_2}{\text -}{{\rm Y}_2}{{\rm O}_3}$TeO-BaF-YO and ${{\rm TeO}_2}$TeO modified fluoroaluminate glasses are fabricated by using a rod-in-tube method.

Wideband multiwavelength Brillouin fiber laser based on dual-mode AlGaInAs/InP microcavity lasers.

A multiwavelength Brillouin fiber laser (BFL) is demonstrated using a 1.55-µm AlGaInAs/InP microcavity laser as a seed source. The combination of a nonlinear fiber cavity and a feedback loop leads to multiwavelength generation with a channel spacing of double-Brillouin-frequency assisted by cavity-enhanced four-wave mixing.

Design of all-solid W-type index fluorotellurite fibers with near-zero-flattened chromatic dispersion for optical frequency comb generation.

All-solid W-type index fluorotellurite fibers (AWFTFs) with near-zero-flattened dispersion profiles are designed for optical frequency comb (OFC) generation. The fiber core and cladding materials are ${{\rm TeO}_2} {\text - } {{\rm BaF}_2} {\text - } {{\rm Y}_2}{{\rm O}_3}$TeO-BaF-YO (TBY) and fluoroaluminate glasses. Those two glasses have large refractive index contrast as well as similar thermal expansion coefficients and softening temperatures.

110 mW single-frequency Yb:YAG crystal-derived silica fiber laser at 1064 nm.

A single-frequency laser based on Yb:YAG crystal-derived silica fiber (YDSF) was demonstrated. The YDSF was fabricated by a molten-core method with a doping concentration of 4.8 wt.