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Full-Text Articles in Physics
A Proof-Of-Principle Experiment Of Optical Injection Of Electrons In Laser-Driven Plasma Waves, N. Saleh, P. Zhang, Shouyuan Chen, Z.-M. Sheng, Anatoly Maksimchuk, V. Yanovsky, Donald P. Umstadter
A Proof-Of-Principle Experiment Of Optical Injection Of Electrons In Laser-Driven Plasma Waves, N. Saleh, P. Zhang, Shouyuan Chen, Z.-M. Sheng, Anatoly Maksimchuk, V. Yanovsky, Donald P. Umstadter
Donald Umstadter Publications
We report on a proof-of-principle experiment that demonstrates, for the first time, the feasibility of optically injecting electrons into laser-driven plasma waves, first proposed by [D. Umstadter, J.-K. Kim, and E. Dodd, Phys. Rev. Lett. 76, 2073 (1996)l. Using a Table-Top-Tera Watt laser system (I ~5x1018 W/cm2, λ = 1 μm, τ = 400 fs), whose output beam is split by 1:4 ratio into a pump and injection beams, respectively, spatial (within 10 μm) and temporal (within 400 fs) overlap of the two beams were achieved by intersecting them orthogonally in an under-dense (~ 4x1019 cm …
Study Of Energetic Ion Generation From High-Intensity-Laser Dense-Plasma Interactions, K. Flippo, Anatoly Maksimchuk, Sudeep Banerjee, K. Nash, V. Wong, T. Lin, K. Nemoto, V. Yu. Bychenkov, Y. Sentoku, G. Mourou, Donald P. Umstadter
Study Of Energetic Ion Generation From High-Intensity-Laser Dense-Plasma Interactions, K. Flippo, Anatoly Maksimchuk, Sudeep Banerjee, K. Nash, V. Wong, T. Lin, K. Nemoto, V. Yu. Bychenkov, Y. Sentoku, G. Mourou, Donald P. Umstadter
Donald Umstadter Publications
We report on the characteristics of an ultrafast-laser driven proton beam from thinfilm targets. The difference in proton beam profiles, beam energies, and laser induced back ablation plumes between a dielectric (Mylar) and a conductor (aluminum) are discussed. Evidence for front-side acceleration and a method for beam manipulation are also presented.
Developments In Relativistic Nonlinear Optics, Donald P. Umstadter, Sudeep Banerjee, Shouyuan Chen, E. Dodd, K. Flippo, Anatoly Maksimchuk, N. Saleh, A. Valenzuela, P. Zhang
Developments In Relativistic Nonlinear Optics, Donald P. Umstadter, Sudeep Banerjee, Shouyuan Chen, E. Dodd, K. Flippo, Anatoly Maksimchuk, N. Saleh, A. Valenzuela, P. Zhang
Donald Umstadter Publications
We report recent results of experiments and simulations in the regime of peak laser intensities above 1019 W/cm2, including the following topics: (1) electron and proton acceleration to energies in excess of 10 MeV in well collimated beams; (2) use of laser chirp to control the growth of plasma waves and acceleration of electrons by the Raman instability; (3) all optical injection and acceleration of electrons; (4) relativistic self-focusing by means of the mutual index of refraction of two overlapping laser pulses; (5) creation of a radioisotope by the reaction 10B(d,n)11C; (6) …
Phase Dependence Of Thomson Scattering In An Ultraintense Laser Field, Fei He, Y. Y. Lau, Donald P. Umstadter, Trevor Strickler
Phase Dependence Of Thomson Scattering In An Ultraintense Laser Field, Fei He, Y. Y. Lau, Donald P. Umstadter, Trevor Strickler
Donald Umstadter Publications
The Thomson scattering spectra of an electron by an ultraintense laser field are computed. It is found that the electron orbit, and therefore its nonlinear Thomson scattering spectra, depend critically on the amplitude of the ultraintense laser field and on the phase at which the electron sees the laser electric field. Contrary to some customary notions, the Thomson scattering spectra, in general, do not occur at integer multiples of the laser frequency and the maximum frequency is proportional to the first instead of the third power of the electric field strength for the case of an ultraintense laser. The implications …
An All Optical Laser Wakefield Electron Injector, Donald Umstadter
An All Optical Laser Wakefield Electron Injector, Donald Umstadter
Donald Umstadter Publications
The personnel who were supported by the grant included the P.I. (Prof. Umstadter), several research scientists (A. Maksimchuk and V. Yanovsky), a postdoc (P. Zhang) and several graduate and undergraduate students.
Although there were several setbacks in developing the novel laser technology required to produce a monoenergetic beam of electrons from an all-optical accelerator, several important steps were taken towards reaching that ultimate goal. The most important outcome of this project was that we demonstrated the principle of optical control of laser accelerators, namely, that one laser pulse could modify the properties (e.g., emittance and electron number) of an electron …
High-Energy Ion Generation In Interaction Of Short Laser Pulse With High-Density Plasma, Y. Sentoku, V. Y. Bychenkov, K. Flippo, Anatoly Maksimchuk, K. Mima, G. Mourou, Z. M. Sheng, Donald Umstadter
High-Energy Ion Generation In Interaction Of Short Laser Pulse With High-Density Plasma, Y. Sentoku, V. Y. Bychenkov, K. Flippo, Anatoly Maksimchuk, K. Mima, G. Mourou, Z. M. Sheng, Donald Umstadter
Donald Umstadter Publications
Multi-MeV ion production from the interaction of a short laser pulse with a high-density plasma, accompanied by an underdense preplasma, has been studied with a particle-in- cell simulation and good agreement is found with experiment. The mechanism primarily responsible for the acceleration of ions is identified. Comparison with experiments sheds light on the ion-energy dependence on laser intensity, preplasma scale length, and relative ion energies for a multi-species plasma. Two regimes of maximum ion-energy dependence on laser intensity, I, have been identified: subrelativistic, μ I ; and relativistic, μ √I. Simulations show that the energy of the …