Self-focusing and de-focusing of intense left and right-hand polarized laser pulse in hot magnetized plasma: Laser out-put power and laser spot-size

Optik ◽  
2017 ◽  
Vol 142 ◽  
pp. 360-369 ◽  
Author(s):  
Mehdi Abedi-Varaki ◽  
Saed Jafari
Keyword(s):  
Laser Pulse ◽  
Spot Size ◽  
Magnetized Plasma ◽  
Laser Spot ◽  
Laser Spot Size ◽  
Plasma Laser ◽  
Self Focusing ◽  
Right Hand ◽  
Left And Right

Nonlinear interaction of intense left- and right-hand polarized laser pulse with hot magnetized plasma

2017 ◽  
Vol 83 (4) ◽  
Author(s):  
M. Abedi-Varaki ◽  
S. Jafari
Keyword(s):  
Magnetic Field ◽  
Laser Pulse ◽  
Plasma Temperature ◽  
Spot Size ◽  
Magnetized Plasma ◽  
Laser Spot Size ◽  
Self Focusing ◽  
Right Hand ◽  
Left And Right ◽  
Oblique Magnetic Field

In this article, self-focusing of an intense circularly polarized laser pulse in the presence of an external oblique magnetic field in hot magnetized plasma, using Maxwell’s equations and the relativistic fluid momentum equation, is studied. An envelope equation governing the spot size of the laser beam for both of left- and right-hand polarizations has been derived and the effects of the plasma temperature and oblique magnetic field on the electron density distribution of hot plasma with respect to variation of the normalized laser spot size has been investigated. Numerical results depict that in right-hand polarization, self-focusing of the laser pulse along the propagation direction in hot magnetized plasma becomes better and more compressed with increasing $\unicode[STIX]{x1D703}$. Inversely, in left-hand polarization, increase of $\unicode[STIX]{x1D703}$ in an oblique magnetic field leads to enhancement of the spot size and reduction self-focusing. Besides, in the plasma density profile, self-focusing of the laser pulse improves in comparison with no oblique magnetic field. Also it is shown that plasma temperature has a key role in the laser spot size, normalized laser output power and the variation of plasma density.

Effect of obliquely external magnetic field on the intense laser pulse propagating in plasma medium

2020 ◽  
Vol 34 (07) ◽  
pp. 2050044
Author(s):  
Mehdi Abedi-Varaki
Keyword(s):  
Magnetic Field ◽  
External Magnetic Field ◽  
Laser Pulse ◽  
Magnetoactive Plasma ◽  
Spot Size ◽  
The Self ◽  
Intense Laser ◽  
Intense Laser Pulse ◽  
Laser Spot Size ◽  
Self Focusing

In this paper, self-focusing of intense laser pulse propagating along the obliquely external magnetic field on the collisional magnetoactive plasma by using the perturbation theory have been studied. The wave equation describing the interaction of intense laser pulse with collisional magnetoactive plasma is derived. In addition, employing source-dependent expansion (SDE) method, the analysis of the laser spot-size is discussed. It is shown that with increasing of the angle in obliquely external magnetic field, the spot-size of laser pulse decreases and as a result laser pulse becomes more focused. Furthermore, it is concluded that the self-focusing quality of the laser pulse has been enhanced due to the presence of obliquely external magnetic field in the collisional magnetoactive plasma. Besides, it is seen that with increasing of [Formula: see text], the laser spot-size reduces and subsequently the self-focusing of the laser pulse in plasma enhances. Moreover, it is found that changing the collision effect in the magnetoactive plasma leads to increases of self-focusing properties.

scholarly journals Relativistic Gaussian laser beam self-focusing in collisional quantum plasmas

2015 ◽  
Vol 33 (3) ◽  
pp. 397-403 ◽  
Author(s):  
S. Zare ◽  
S. Rezaee ◽  
E. Yazdani ◽  
A. Anvari ◽  
R. Sadighi-Bonabi
Keyword(s):  
Laser Beam ◽  
Laser Energy ◽  
Oscillation Amplitude ◽  
Beam Width ◽  
Spot Size ◽  
Collisional Plasma ◽  
Laser Spot ◽  
Quantum Plasma ◽  
Laser Spot Size ◽  
Self Focusing

AbstractPropagation of Gaussian X-ray laser beam is presented in collisional quantum plasma and the beam width oscillation is studied along the propagation direction. It is noticed that due to energy absorption in collisional plasma, the laser energy drops to an amount less than the critical value of the self-focusing effect and consequently, the laser beam defocuses. It is found that the oscillation amplitude of the laser spot size enhances while passing through collisional plasma. For the greater values of collision frequency, the beam width oscillates with higher amplitude and defocuses in a shallower plasma depth. Also, it is realized that in a dense plasma environment, the laser self-focusing occurs earlier with the higher oscillation amplitude, smaller laser spot size and more oscillations.

CONTROLLING THE REMOTE IONIZATION DISTANCE BY A LINEARLY CHIRPED FEMTOSECOND LASER PULSE IN AIR

2012 ◽  
Vol 21 (04) ◽  
pp. 1250046
Author(s):  
F. SOHBATZADEH ◽  
S. P. HOSSEINI
Keyword(s):  
Laser Pulse ◽  
Velocity Dispersion ◽  
Group Velocity Dispersion ◽  
Pulse Length ◽  
Spot Size ◽  
Pulse Profile ◽  
Laser Spot Size ◽  
Focal Distance ◽  
Self Focusing ◽  
Chirped Laser Pulse

In this paper, propagation of a linearly chirped laser pulse in air was investigated to control the remote ionization distance, numerically. Laser spot size and pulse length will be obtained versus effective initial parameters such as positive and negative initial chirp. It is seen that the initial chirp parameter and primary curvature of wave front have important role in focal distance variation and remote ionization. It was also shown that the group velocity dispersion (GVD) could alter and split the positively chirped laser pulse profile after nonlinear self-focusing.

Modelling of the laser spot size dependence of retinal thermal damage

2005 ◽  
Author(s):  
Karl Schulmeister ◽  
Bernhard Seiser ◽  
Florian Edthofer ◽  
David J. Lund
Keyword(s):  
Size Dependence ◽  
Thermal Damage ◽  
Spot Size ◽  
Laser Spot ◽  
Laser Spot Size

scholarly journals Long lifetime of bialkali photocathodes operating in high gradient superconducting radio frequency gun

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
E. Wang ◽  
V. N. Litvinenko ◽  
I. Pinayev ◽  
M. Gaowei ◽  
J. Skaritka ◽  
...  
Keyword(s):  
Radio Frequency ◽  
Electron Beams ◽  
Spot Size ◽  
Laser Spot ◽  
Laser Spot Size ◽  
High Quantum Efficiency ◽  
High Brightness ◽  
High Charge ◽  
Superconducting Radio Frequency ◽  
Long Lifetime

AbstractHigh brightness, high charge electron beams are critical for a number of advanced accelerator applications. The initial emittance of the electron beam, which is determined by the mean transverse energy (MTE) and laser spot size, is one of the most important parameters determining the beam quality. The bialkali photocathodes illuminated by a visible laser have the advantages of high quantum efficiency (QE) and low MTE. Furthermore, Superconducting Radio Frequency (SRF) guns can operate in the continuous wave (CW) mode at high accelerating gradients, e.g. with significant reduction of the laser spot size at the photocathode. Combining the bialkali photocathode with the SRF gun enables generation of high charge, high brightness, and possibly high average current electron beams. However, integrating the high QE semiconductor photocathode into the SRF guns has been challenging. In this article, we report on the development of bialkali photocathodes for successful operation in the SRF gun with months-long lifetime while delivering CW beams with nano-coulomb charge per bunch. This achievement opens a new era for high charge, high brightness CW electron beams.

Laser spot size and scaling laws for laser beam additive manufacturing

2022 ◽  
Vol 73 ◽  
pp. 26-39
Author(s):  
Jordan S. Weaver ◽  
Jarred C. Heigel ◽  
Brandon M. Lane
Keyword(s):  
Additive Manufacturing ◽  
Laser Beam ◽  
Scaling Laws ◽  
Spot Size ◽  
Laser Spot ◽  
Laser Spot Size

Evaluation of SEE on a 32-bit Microprocessor by Laser Test and Heavy Ion Test

2015 ◽  
Vol 1105 ◽  
pp. 391-396
Author(s):  
Chun Qing Yu ◽  
Long Fan ◽  
Suge Yue ◽  
Jian Hua Ma ◽  
Hong Chao Zheng
Keyword(s):  
Laser Pulse ◽  
Low Cost ◽  
Step Length ◽  
Heavy Ion ◽  
Spot Size ◽  
Single Event ◽  
Laser Spot Size ◽  
Scanning Step ◽  
Instruction Pipeline ◽  
Made In

In this paper the SEE (single event effects) of different parts of device were explored on a 32-bit microprocessor with a five-stage instruction pipeline by laser test and heavy ion test. The cross section curves for different function units were obtained and the comparison of the dates obtained from laser test and heavy ion tests was made. In addition, laser test under different scanning steps were made which indicate that when the scanning step length is in small steps which is considerably equivalent to the laser spot size, there is little change in the number of single event errors caused by each laser pulse. Wherever with the scanning step increasing, the number of single event errors caused by each laser pulse will be reduced. Experiment results suggest that there are differences between laser test and the heavy ion test but have a similar trend. The pulsed laser is an extremely powerful and low-cost technique for SEE testing and will provide invaluable information in characterizing SEE in integrate circuits.

Sign in / Sign up

Export Citation Format

Share Document