Monolithic waveguide laser mode-locked by embedded Ag nanoparticles operating at 1 μm

AbstractMonolithic waveguide laser devices are required to achieve on-chip lasing. In this work, a new design of a monolithic device with embedded Ag nanoparticles (NPs) plus the Nd:YAG ridge waveguide has been proposed and implemented. By using Ag+ ion implantation, the embedded Ag NPs are synthesized on the near-surface region of the Nd:YAG crystal, resulting in the significant enhancement of the optical nonlinearity of Nd:YAG and offering saturable absorption properties of the crystal at a wide wavelength band. The subsequent processing of the O5+ ion implantation and diamond saw dicing of crystal finally leads to the fabrication of monolithic waveguide with embedded Ag NPs. Under an optical pump, the Q-switched mode-locked waveguide lasers operating at 1 μm is realized with the pulse duration of 29.5 ps and fundamental repetition rate of 10.53 GHz, owing to the modulation of Ag NPs through evanescent field interaction with waveguide modes. This work introduces a new approach in the application of monolithic ultrafast laser devices by using embedded metallic NPs.

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Silver Nanoparticles under Nanosecond Pulsed Laser Excitation as an Intensity Sensitive Saturable Absorption to Reverse Saturable Absorption Switching Material

Photonics ◽

10.3390/photonics8100413 ◽

2021 ◽

Vol 8 (10) ◽

pp. 413

Author(s):

Edappadikkunnummal Shiju ◽

Kaniyarakkal Sharafudeen ◽

T. M. Remya ◽

N. K. Siji Narendran ◽

Palengara Sudheesh ◽

...

Keyword(s):

Silver Nanoparticles ◽

Nonlinear Optical ◽

Second Harmonic ◽

Laser System ◽

Laser Pulses ◽

Optical Nonlinearity ◽

Saturable Absorption ◽

Reverse Saturable Absorption ◽

Closed Aperture ◽

Ag Nps

Optical nonlinearity involved switching draws an important consideration in nonlinear optical studies. Based on that, we explored nonlinear absorption processes in silver nanoparticles synthesized by liquid phase laser ablation technique employing a second harmonic wavelength (532 nm) of Q switched Nd:YAG laser pulses with 7 ns pulse width and 10 Hz repetition rates. The typical surface plasmon resonance induced absorption (~418 nm) confirmed the formation of Ag NPs. The Z-scan technique was used to study the nonlinear optical processes, employing the same laser system used for ablation. Our study reveals that there is an occurrence of a saturable to reverse saturable absorption switching activity in the Ag nanoparticles, which is strongly on-axis input intensity dependent as well. The closed aperture Z-scan analysis revealed the self-defocusing nature of the sample.

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Silver Nanoparticles in Porous Germanium

Advances in Nanoscience and Nanotechnology ◽

10.33140/ann.03.03.03 ◽

2019 ◽

Vol 3 (3) ◽

Keyword(s):

Ion Implantation ◽

Ag Nanoparticles ◽

Average Diameter ◽

Size Distribution Function ◽

Thin Layers ◽

Low Energy ◽

High Dose ◽

Near Surface ◽

Backscattered Electrons ◽

20 Nm

Recent experiments on fabrication of nanoporous Si and Ge layers with Ag nanoparticles by low-energy high-dose ion implantation are discussed. Ag+-ion implantation of single-crystal c-Si and c-Ge at low-energy (E = 30 keV) highdoses (D = 1.25·1015 - 1.5·1017 ion/cm2 ) and current density (J = 2-15 μA/cm2 ) was carried out for this purpose. The changes of Si and Ge surface morphology after ion implantation were studied by scanning electron and atom-force microscopy. The near surface area of samples was also analyzed by diffraction of the backscattered electrons and energydispersive X-ray microanalysis. Amorphization of near-surface layer was observed at the lowest implantation doses of c-Si. Ag nanoparticles were synthesized and uniformly distributed over the near Si surface when the threshold dose of 3.1·1015 ion/cm2 exceeded. At a dose of more than 1017 ion/cm2 , the formation of a surface nanoporous PSi structure was detected. Ag nanoparticle size distribution function became bimodal and the largest particles were localized along Si-pore walls. In the case of Ge substrates, as a result of the implantation on the c-Ge surface, a porous amorphous PGe layer of a spongy structure was formed consisting of a network of intersecting Ge nanowires with an average diameter of ~ 10-20 nm. At the ends of the nanowires, the synthesis of Ag nanoparticles was observed. It was found that the formation of pores during Ag+-ion implantation was accompanied by efficient spattering of the Si and Ge surface. Thus, ion implantation is suggested to be used for the formation of nanoporous semiconductor thin layers for industry, which could be easily combined with the crystalline matrix for various applications.

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Controlling size and distribution of Ag nanoparticles in near surface of SiO2 glass by low-energy ion implantation

Materials Express ◽

10.1166/mex.2021.2115 ◽

2021 ◽

Vol 11 (12) ◽

pp. 2010-2014

Author(s):

Xiaodong Zhou ◽

Erlei Wang ◽

Sihua Zhou ◽

Honglei Yuan ◽

Yongmei Wang ◽

...

Keyword(s):

Grain Size ◽

Ion Implantation ◽

Metal Nanoparticles ◽

Plasmon Resonance ◽

Ag Nanoparticles ◽

Resonance Effect ◽

Low Energy ◽

Implantation Energy ◽

Near Surface ◽

Implantation Method

Ag nanoparticles were embedded in the near surface of SiO2 substrate and fabricated by low-energy ion implantation method in this study. The optical and structural properties of Ag implanted samples were investigated using optical spectroscopy, transmission electron microscope (TEM) and atomic force microscopy (AFM). The grain size and distribution of nanoparticles embedded in the substrate were characterized by TEM and AFM characterization. Results showed that the grain size and depth of distribution of nanoparticles were controlled by changing the ion implantation energy and dose. Furthermore, the Ag nanoparticles embedded near surface of substrate prepared by this low-energy ion implantation method had strong local surface plasmon resonance (LSPR) characteristics. Our work demonstrates a practical means for fabrication of metal nanoparticles with controllable size and distribution using ion implantation technology, which is helpful to the application of local plasmon resonance effect of metal nanoparticles.

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The Effects of Ion Implantation on the Surface Features of Inconel 600

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100118333 ◽

1985 ◽

Vol 43 ◽

pp. 288-289

Author(s):

John D. Rubio

Keyword(s):

Grain Boundary ◽

Ion Implantation ◽

Nuclear Power ◽

Power Plants ◽

Surface Region ◽

Selective Dissolution ◽

Boundary Region ◽

Near Surface ◽

Inconel 600 ◽

Steam Generator Tubing

The degradation of steam generator tubing at nuclear power plants has become an important problem for the electric utilities generating nuclear power. The material used for the tubing, Inconel 600, has been found to be succeptible to intergranular attack (IGA). IGA is the selective dissolution of material along its grain boundaries. The author believes that the sensitivity of Inconel 600 to IGA can be minimized by homogenizing the near-surface region using ion implantation. The collisions between the implanted ions and the atoms in the grain boundary region would displace the atoms and thus effectively smear the grain boundary.To determine the validity of this hypothesis, an Inconel 600 sample was implanted with 100kV N2+ ions to a dose of 1x1016 ions/cm2 and electrolytically etched in a 5% Nital solution at 5V for 20 seconds. The etched sample was then examined using a JEOL JSM25S scanning electron microscope.

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Analytical Electron Microscopy of Ion-Implanted Metals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010011831x ◽

1985 ◽

Vol 43 ◽

pp. 282-285

Author(s):

D.I. Potter ◽

M. Ahmed ◽

K. Ruffing

Keyword(s):

Electron Microscopy ◽

Ion Implantation ◽

Friction And Wear ◽

Analytical Electron Microscopy ◽

Chemical Compositions ◽

Surface Chemical ◽

Near Surface ◽

The Past ◽

Analytical Electron ◽

Property Changes

Ion implantation, used extensively for the past decade in fabricating semiconductor devices, now provides a unique means for altering the near-surface chemical compositions and microstructures of metals. These alterations often significantly improve physical properties that depend on the surface of the material; for example, catalysis, corrosion, oxidation, hardness, friction and wear. Frequently the mechanisms causing these beneficial alterations and property changes remain obscure and much of the current research in the area of ion implantation metallurgy is aimed at identifying such mechanisms. Investigators thus confront two immediate questions: To what extent is the chemical composition changed by implantation? What is the resulting microstructure? These two questions can be investigated very fruitfully with analytical electron microscopy (AEM), as described below.

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Ag Nanoparticles Sensitized In2O3 Nanograin for the Ultrasensitive HCHO Detection at Room Temperature

Nanoscale Research Letters ◽

10.1186/s11671-019-3213-6 ◽

2019 ◽

Vol 14 (1) ◽

Cited By ~ 6

Author(s):

Shiqiang Zhou ◽

Mingpeng Chen ◽

Qingjie Lu ◽

Yumin Zhang ◽

Jin Zhang ◽

...

Keyword(s):

Indoor Air ◽

Ag Nanoparticles ◽

Room Temperature ◽

Unsolved Problem ◽

Air Pollutant ◽

Ag Nps ◽

Performance Targets ◽

Fabrication Cost ◽

Low Concentrations ◽

Stringent Performance

AbstractFormaldehyde (HCHO) is the main source of indoor air pollutant. HCHO sensors are therefore of paramount importance for timely detection in daily life. However, existing sensors do not meet the stringent performance targets, while deactivation due to sensing detection at room temperature, for example, at extremely low concentration of formaldehyde (especially lower than 0.08 ppm), is a widely unsolved problem. Herein, we present the Ag nanoparticles (Ag NPs) sensitized dispersed In2O3 nanograin via a low-fabrication-cost hydrothermal strategy, where the Ag NPs reduces the apparent activation energy for HCHO transporting into and out of the In2O3 nanoparticles, while low concentrations detection at low working temperature is realized. The pristine In2O3 exhibits a sluggish response (Ra/Rg = 4.14 to 10 ppm) with incomplete recovery to HCHO gas. After Ag functionalization, the 5%Ag-In2O3 sensor shows a dramatically enhanced response (135) with a short response time (102 s) and recovery time (157 s) to 1 ppm HCHO gas at 30 °C, which benefits from the Ag NPs that electronically and chemically sensitize the crystal In2O3 nanograin, greatly enhancing the selectivity and sensitivity.

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