Investigating the Threshold Conditions of Air Breakdown with Mode-Locked Q-Switched Laser Pulses, and the Temporal Dynamics of Induced Plasma with Self-Scattering Phenomenon

A Q-switched Nd:YAG laser with mode-locked modulations is utilized to explore the laser-induced air breakdown. The various modulation depths of the mode-locking within the Q-switched pulse can be utilized to investigate the threshold conditions. With the GHz high-speed detectors to accurately measure the temporal pulse shape pulse by pulse, it is verified that the air breakdown threshold is crucially determined by the peak-power density instead of the energy density from the statistic results, especially for mode-locked Q-switched lasers. The stability of the system for laser-induced breakdown can be evaluated by threshold width through fitting the statistical result. Otherwise, by measuring the temporal characteristics of the excitation pulse and the induced plasma, it is further found that the plasma radiation displays a few-nanoseconds time delay to the excitation pulse and shows a decaying tail to be 10 times longer than the plasma build-up time. Moreover, the incident laser pulse is observed to be self-scattered by the air breakdown, and a rapidly modulated scattering rate is found with a slight delay time to the excitation mode-locked subpulse modulations.

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Exploring Air Breakdown Threshold and Temporal Dynamics by a Q-switched Mode-locked Nd:YAG Laser in a Statistical Approach

Advanced Solid State Lasers ◽

10.1364/assl.2015.am5a.4 ◽

2015 ◽

Author(s):

P. H. Tuan ◽

C. Y. Cho ◽

C. H. Wu ◽

J. C. Tung ◽

K. W. Su ◽

...

Keyword(s):

Nd:Yag Laser ◽

Statistical Approach ◽

Temporal Dynamics ◽

Breakdown Threshold ◽

Air Breakdown

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Dual-shot dynamics and ultimate frequency of all-optical magnetic recording on GdFeCo

Light Science & Applications ◽

10.1038/s41377-020-00451-z ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

Sicong Wang ◽

Chen Wei ◽

Yuanhua Feng ◽

Hongkun Cao ◽

Wenzhe Li ◽

...

Keyword(s):

Magnetization Reversal ◽

Energy Efficient ◽

High Speed ◽

Data Transfer ◽

Laser Pulses ◽

Time Resolved ◽

All Optical ◽

Fs Laser ◽

High Speed Data ◽

Natural Way

AbstractAlthough photonics presents the fastest and most energy-efficient method of data transfer, magnetism still offers the cheapest and most natural way to store data. The ultrafast and energy-efficient optical control of magnetism is presently a missing technological link that prevents us from reaching the next evolution in information processing. The discovery of all-optical magnetization reversal in GdFeCo with the help of 100 fs laser pulses has further aroused intense interest in this compelling problem. Although the applicability of this approach to high-speed data processing depends vitally on the maximum repetition rate of the switching, the latter remains virtually unknown. Here we experimentally unveil the ultimate frequency of repetitive all-optical magnetization reversal through time-resolved studies of the dual-shot magnetization dynamics in Gd27Fe63.87Co9.13. Varying the intensities of the shots and the shot-to-shot separation, we reveal the conditions for ultrafast writing and the fastest possible restoration of magnetic bits. It is shown that although magnetic writing launched by the first shot is completed after 100 ps, a reliable rewriting of the bit by the second shot requires separating the shots by at least 300 ps. Using two shots partially overlapping in space and minimally separated by 300 ps, we demonstrate an approach for GHz magnetic writing that can be scaled down to sizes below the diffraction limit.

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Optical Waveguides Embedded in PCBs - A Real World Application of 3D Structures Written by TPA

MRS Proceedings ◽

10.1557/proc-1054-ff01-04 ◽

2007 ◽

Vol 1054 ◽

Cited By ~ 3

Author(s):

Ruth Houbertz ◽

Herbert Wolter ◽

Volker Schmidt ◽

Ladislav Kuna ◽

Valentin Satzinger ◽

...

Keyword(s):

Optical Fibers ◽

Optical Waveguides ◽

High Speed ◽

Printed Circuit Boards ◽

Data Transfer ◽

Laser Pulses ◽

Photon Absorption ◽

Optical Data ◽

Direct Laser ◽

High Speed Data

ABSTRACTThe integration of optical interconnects in printed circuit boards (PCB) is a rapidly growing field worldwide due to a continuously increasing need for high-speed data transfer. There are any concepts discussed, among which are the integration of optical fibers or the generation of waveguides by UV lithography, embossing, or direct laser writing. The devices presented so far require many different materials and process steps, but particularly also highly-sophisticated assembly steps in order to couple the optoelectronic elements to the generated waveguides. In order to overcome these restrictions, an innovative approach is presented which allows the embedding of optoelectronic components and the generation of optical waveguides in only one optical material. This material is an inorganic-organic hybrid polymer, in which the waveguides are processed by two-photon absorption (TPA) processes, initiated by ultra-short laser pulses. In particular, due to this integration and the possibility ofin situpositioning the optical waveguides with respect to the optoelectronic components by the TPA process, no complex packaging or assembly is necessary. Thus, the number of necessary processing steps is significantly reduced, which also contributes to the saving of resources such as energy or solvents. The material properties and the underlying processes will be discussed with respect to optical data transfer in PCBs.

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Influence of hot electrons on the spectra of iron plasma irradiated by femtosecond laser pulses with 1021 W/cm2 intensities

Laser and Particle Beams ◽

10.1017/s026303461600077x ◽

2017 ◽

Vol 35 (1) ◽

pp. 92-99 ◽

Cited By ~ 3

Author(s):

A. Stafford ◽

A.S. Safronova ◽

A.Ya. Faenov ◽

T.A. Pikuz ◽

R. Kodama ◽

...

Keyword(s):

Laser Pulses ◽

Time Frame ◽

Femtosecond Laser Pulses ◽

Hot Electrons ◽

Plasma Radiation ◽

X Ray ◽

Laser Plasma Interaction ◽

Multiply Charged ◽

Interaction Experiment ◽

Charged Ions

AbstractThe use of laboratory experiments as plasma creating sources is a valuable tool for understanding astrophysical observations. Recently plasma created through irradiation by lasers with relativistic intensities has been used to study effects of hot electrons and X-ray pumping on X-ray formation of multiply charged ions spectra. This paper discusses the formation of K-shell Fe spectra recorded from a plasma irradiated by 35 fs pulses with intensities of 1021 W/cm2. Modeling of the spectra suggests three different regions of plasma radiation including a cold ~10 eV region, a mild ~700 eV region, and a hot ~3500 eV region. The influence of hot electrons and X-ray pumping is discussed and a comparison with K-shell Fe spectra from a 1 MA X-pinch experiment is included to highlight the differences due to the shorter time frame of the laser–plasma interaction experiment.

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Beam-homogenization and space-charge–broadening calibration for accurately measuring high-intensity laser pulses using a high-speed streak camera

Conference on Lasers and Electro-Optics 2012 ◽

10.1364/cleo_si.2012.cm4d.8 ◽

2012 ◽

Cited By ~ 1

Author(s):

J. Qiao ◽

P. A. Jaanimagi ◽

R. Boni ◽

J. Bromage ◽

E. Hill

Keyword(s):

Space Charge ◽

High Intensity ◽

High Speed ◽

Streak Camera ◽

Laser Pulses ◽

High Intensity Laser ◽

Intensity Laser

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Experiment Research of Laser Induced Air Breakdown

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.599-601.201 ◽

2014 ◽

Vol 599-601 ◽

pp. 201-204

Author(s):

Hai Dong Wu

Keyword(s):

Energy Conversion ◽

High Speed ◽

Laser Excitation ◽

Laser Energy ◽

Ionization Process ◽

High Speed Camera ◽

Experiment Research ◽

Sound Energy ◽

Air Breakdown

The principle of laser induced air breakdown was introduced. The laser energy conversion in ionization process was studied. The phenomenon of laser induced air breakdown was observed by using high speed camera. It was found that a higher laser energy induced more laser energy to transfer into light and sound energy. The plasma reached maximum in shape in about 20 to 30 ns after laser excitation, and disappeared in about 16μs.

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Ultrafast electro-optic light with subcycle control

Science ◽

10.1126/science.aat6451 ◽

2018 ◽

Vol 361 (6409) ◽

pp. 1358-1363 ◽

Cited By ~ 43

Author(s):

David R. Carlson ◽

Daniel D. Hickstein ◽

Wei Zhang ◽

Andrew J. Metcalf ◽

Franklyn Quinlan ◽

...

Keyword(s):

High Speed ◽

Near Infrared ◽

Continuous Wave ◽

Mode Locking ◽

Light Sources ◽

Electro Optic ◽

High Pulse ◽

Optical Cycle ◽

Rapid Transients ◽

And Control

Light sources that are ultrafast and ultrastable enable applications like timing with subfemtosecond precision and control of quantum and classical systems. Mode-locked lasers have often given access to this regime, by using their high pulse energies. We demonstrate an adaptable method for ultrastable control of low-energy femtosecond pulses based on common electro-optic modulation of a continuous-wave laser light source. We show that we can obtain 100-picojoule pulse trains at rates up to 30 gigahertz and demonstrate sub–optical cycle timing precision and useful output spectra spanning the near infrared. Our source enters the few-cycle ultrafast regime without mode locking, and its high speed provides access to nonlinear measurements and rapid transients.

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