Laser damage studies of silicon surfaces using ultra-short laser pulses
- A. Singh, A. Kapoor, K. Tripathi, G. Kumar
- Materials Science, Physics
- 1 February 2002
Picosecond optical nonlinearity in monolayer-protected gold, silver, and gold-silver alloy nanoclusters
- R. Philip, G. Kumar, N. Sandhyarani, T. Pradeep
- Physics
- 15 November 2000
Monolayer-protected Au, Ag, and Au:Ag alloy nanoclusters have been synthesized using octanethiol and octadecanethiol as capping agents. The particle-size distribution is narrow with an average core…
Highly efficient broadband terahertz generation from ultrashort laser filamentation in liquids
This work demonstrates the generation of terahertz radiation via ultrashort pulse induced filamentation in liquids with an order of magnitude higher energy than from conventional two-color filamentations in air.
Metal nanoplasmas as bright sources of hard X-ray pulses.
- P. P. Rajeev, P. Taneja, P. Ayyub, A. Sandhu, G. Kumar
- PhysicsPhysical Review Letters
- 9 April 2002
The authors' experiments show a 13-fold enhancement in hard x-ray yield emitted by copper nanoparticle plasmas formed at the focal volume and a simple model explains the observed enhancement quantitatively and provides pointers to the design of structured surfaces for maximizing such emissions.
Near-complete absorption of intense, ultrashort laser light by sub-lambda gratings.
This study demonstrates near-100% light absorption and increased x-ray emission from dense plasmas created on solid surfaces with a periodic sub-lambda structure and offers a definite, quantitative way forward for optimizing and understanding the absorption process.
Laser-generated ultrashort multimegagauss magnetic pulses in plasmas.
- A. Sandhu, A. Dharmadhikari, P. Kaw
- PhysicsPhysical Review Letters
- 15 April 2002
The first direct observations of anomalously rapid damping of plasma shielding currents produced in response to the hot electron currents penetrating the bulk plasma are presented.
Plasma devices to guide and collimate a high density of MeV electrons
- R. Kodama, Y. Sentoku, T. Yabuuchi
- PhysicsNature
- 23 December 2004
High-conductivity devices consisting of transient plasmas that increase the energy density of MeV electrons generated in laser–matter interactions by more than one order of magnitude hold promise for applications using high energy-density particles and should trigger growth in charged particle optics.
Polarimetric detection of laser induced ultrashort magnetic pulses in overdense plasma
The interaction of intense (∼1016 W cm−2), subpicosecond pulses with solid targets can generate highly directional jets of hot electrons. These electrons can propagate in the solid along with the…
High-contrast interference pattern of amplified spontaneous emission from dyes under transient grating excitation.
- J. Dharmadhikari, A. Dharmadhikari, G. Kumar
- PhysicsOptics Letters
- 1 April 2005
We demonstrate a high-contrast interference fringe pattern formed by amplified spontaneous emission (ASE) in a noncollinear two-beam self-diffraction setup by use of dyes. In the presence of a…
Propensity of molecules to spatially align in intense light fields
- S. Banerjee, D. Mathur, G. Kumar
- Physics, Biology
- 26 April 2000
All molecules can be aligned, even those with the smallest static polarizability, when subjected to ultrashort pulses of sufficient intensity, as well as enhanced ionization and hyperpolarizability.
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