Compact wavelength tunable output around 440 nm pulsed laser for oceanic lidar application

2021 ◽  
Vol 485 ◽  
pp. 126706
Author(s):  
Jiale Zhang ◽  
Jian Ma ◽  
Tingting Lu ◽  
Dong Liu ◽  
Xiaolei Zhu ◽  
...  
Keyword(s):  
Pulsed Laser ◽  
Wavelength Tunable

Wavelength-Tunable Broadband Frequency-Domain OCT Source Based on Spatially Filtered Sub-10-fs Pulsed Laser

2008 ◽  
Vol 20 (12) ◽  
pp. 994-996
Author(s):  
Tae Joong Eom ◽  
Jae Hee Sung ◽  
Chul-Sik Kee ◽  
Do-Kyeong Ko ◽  
Jongmin Lee ◽  
...  
Keyword(s):  
Frequency Domain ◽  
Pulsed Laser ◽  
Wavelength Tunable ◽  
Broadband Frequency

MoTe2-Based Broadband Wavelength Tunable Eye-Safe Pulsed Laser Source at $1.9~\mu$ m

2018 ◽  
Vol 30 (21) ◽  
pp. 1890-1893 ◽  
Author(s):  
Yuzhao Zhang ◽  
Jiawei Wang ◽  
Xiaofeng Guan ◽  
Bin Xu ◽  
Huiying Xu ◽  
...  
Keyword(s):  
Pulsed Laser ◽  
Laser Source ◽  
Wavelength Tunable

scholarly journals Mechanism of transient photothermal inactivation of bacteria using a wavelength-tunable nanosecond pulsed laser

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ichiro Tatsuno ◽  
Yuna Niimi ◽  
Makoto Tomita ◽  
Hiroshi Terashima ◽  
Tadao Hasegawa ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Optical Absorption ◽  
Laser Irradiation ◽  
Pulsed Laser ◽  
Wavelength Tunable ◽  
Photothermal Heating ◽  
Pathogenic Viruses ◽  
Site Selective ◽  
Inactivation Of Bacteria ◽  
Pulsed Laser Irradiation

AbstractThere is a great demand for novel disinfection technologies to inactivate various pathogenic viruses and bacteria. In this situation, ultraviolet (UVC) disinfection technologies seem to be promising because biocontaminated air and surfaces are the major media for disease transmission. However, UVC is strongly absorbed by human cells and protein components; therefore, there are concerns about damaging plasma components and causing dermatitis and skin cancer. To avoid these concerns, in this study, we demonstrate that the efficient inactivation of bacteria is achieved by visible pulsed light irradiation. The principle of inactivation is based on transient photothermal heating. First, we provide experimental confirmation that extremely high temperatures above 1000 K can be achieved by pulsed laser irradiation. Evidence of this high temperature is directly confirmed by melting gold nanoparticles (GNPs). Inorganic GNPs are used because of their well-established thermophysical properties. Second, we show inactivation behaviour by pulsed laser irradiation. This inactivation behaviour cannot be explained by a simple optical absorption effect. We experimentally and theoretically clarify this inactivation mechanism based on both optical absorption and scattering effects. We find that scattering and absorption play an important role in inactivation because the input irradiation is inherently scattered by the bacteria; therefore, the dose that bacteria feel is reduced. This scattering effect can be clearly shown by a technique that combines stained Escherichia coli and site selective irradiation obtained by a wavelength tunable pulsed laser. By measuring Live/Dead fluorescence microscopy images, we show that the inactivation attained by the transient photothermal heating is possible to instantaneously and selectively kill microorganisms such as Escherichia coli bacteria. Thus, this method is promising for the site selective inactivation of various pathogenic viruses and bacteria in a safe and simple manner.

Observations on the growth of YBa2Cu3O7-δ thin films on MgO by pulsed-laser ablation

1991 ◽  
Vol 49 ◽  
pp. 1068-1069
Author(s):  
M. Grant Norton ◽  
C. Barry Carter
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Laser Ablation ◽  
Substrate Surface ◽  
Pulsed Laser ◽  
Pulsed Laser Ablation ◽  
Thin Film Deposition ◽  
Film Deposition ◽  
Laser Ablation Process ◽  
Deposition Parameters

Pulsed-laser ablation has been widely used to produce high-quality thin films of YBa2Cu3O7-δ on a range of substrate materials. The nonequilibrium nature of the process allows congruent deposition of oxides with complex stoichiometrics. In the high power density regime produced by the UV excimer lasers the ablated species includes a mixture of neutral atoms, molecules and ions. All these species play an important role in thin-film deposition. However, changes in the deposition parameters have been shown to affect the microstructure of thin YBa2Cu3O7-δ films. The formation of metastable configurations is possible because at the low substrate temperatures used, only shortrange rearrangement on the substrate surface can occur. The parameters associated directly with the laser ablation process, those determining the nature of the process, e g. thermal or nonthermal volatilization, have been classified as ‘primary parameters'. Other parameters may also affect the microstructure of the thin film. In this paper, the effects of these ‘secondary parameters' on the microstructure of YBa2Cu3O7-δ films will be discussed. Examples of 'secondary parameters' include the substrate temperature and the oxygen partial pressure during deposition.

Microanalysis of silicate glass films grown on α-Al2O3 by pulsed-laser deposition

1993 ◽  
Vol 51 ◽  
pp. 438-439
Author(s):  
Michael P. Mallamaci ◽  
James Bentley ◽  
C. Barry Carter
Keyword(s):  
Liquid Phase ◽  
Single Crystal ◽  
Pulsed Laser Deposition ◽  
Pulsed Laser ◽  
Ceramic Materials ◽  
Laser Deposition ◽  
Triple Junctions ◽  
Ion Milling ◽  
Multicomponent Oxides ◽  
Glass Films

Glass-oxide interfaces play important roles in developing the properties of liquid-phase sintered ceramics and glass-ceramic materials. Deposition of glasses in thin-film form on oxide substrates is a potential way to determine the properties of such interfaces directly. Pulsed-laser deposition (PLD) has been successful in growing stoichiometric thin films of multicomponent oxides. Since traditional glasses are multicomponent oxides, there is the potential for PLD to provide a unique method for growing amorphous coatings on ceramics with precise control of the glass composition. Deposition of an anorthite-based (CaAl2Si2O8) glass on single-crystal α-Al2O3 was chosen as a model system to explore the feasibility of PLD for growing glass layers, since anorthite-based glass films are commonly found in the grain boundaries and triple junctions of liquid-phase sintered α-Al2O3 ceramics.Single-crystal (0001) α-Al2O3 substrates in pre-thinned form were used for film depositions. Prethinned substrates were prepared by polishing the side intended for deposition, then dimpling and polishing the opposite side, and finally ion-milling to perforation.

TEM sample preparation of wear-tested room-temperature pulsed-laser-deposited thin films of MoS2 by ultramicrotomy

1993 ◽  
Vol 51 ◽  
pp. 1118-1119
Author(s):  
Pamela F. Lloyd ◽  
Scott D. Walck
Keyword(s):  
Thin Films ◽  
Sample Preparation ◽  
Room Temperature ◽  
High Vacuum ◽  
Pulsed Laser ◽  
Ultra High Vacuum ◽  
Wear Testing ◽  
Preparation Technique ◽  
Cross Sectional ◽  
Aerospace Applications

Pulsed laser deposition (PLD) is a novel technique for the deposition of tribological thin films. MoS2 is the archetypical solid lubricant material for aerospace applications. It provides a low coefficient of friction from cryogenic temperatures to about 350°C and can be used in ultra high vacuum environments. The TEM is ideally suited for studying the microstructural and tribo-chemical changes that occur during wear. The normal cross sectional TEM sample preparation method does not work well because the material’s lubricity causes the sandwich to separate. Walck et al. deposited MoS2 through a mesh mask which gave suitable results for as-deposited films, but the discontinuous nature of the film is unsuitable for wear-testing. To investigate wear-tested, room temperature (RT) PLD MoS2 films, the sample preparation technique of Heuer and Howitt was adapted.Two 300 run thick films were deposited on single crystal NaCl substrates. One was wear-tested on a ball-on-disk tribometer using a 30 gm load at 150 rpm for one minute, and subsequently coated with a heavy layer of evaporated gold.

Long-Pulsed Laser Speeds Ecchymosis Healing

2009 ◽  
Vol 40 (6) ◽  
pp. 32
Author(s):  
MIRIAM E. TUCKER
Keyword(s):  
Pulsed Laser

Pulsed-Laser Ultrasound Generation in Graphite/Epoxy Plate

2000 ◽  
Vol 12 (1) ◽  
pp. 191-215 ◽  
Author(s):  
A. Rezaizadeh ◽  
J. C. Duke
Keyword(s):  
Pulsed Laser ◽  
Laser Ultrasound
Sign in / Sign up

Export Citation Format

Share Document