99 citations · 488 across the 12 of their papers we have counts for
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Absolute measurement of the ultrafast nonlinear electronic and rovibrational response in H and D
J. K. Wahlstrand, S. Zahedpour, Y. -H. Cheng +2
The electronic, rotational, and vibrational components of the ultrafast optical nonlinearity in H and D are measured directly and absolutely at intensities up to the ioniza…
Sensitivity of propagation and energy deposition in femtosecond filamentation to the nonlinear refractive index
E. W. Rosenthal, J. P. Palastro, N. Jhajj +3
The axial dependence of femtosecond filamentation in air is measured under conditions of varying laser pulsewidth, energy, and focusing f-number. Filaments are characterized by the…
Collection of remote optical signals by air waveguides
E. W. Rosenthal, N. Jhajj, J. K. Wahlstrand +1
Collection of weak signals from remote locations is the primary goal and the primary hurdle of optical stand-off detection schemes. Typically, the measured signal is enhanced using…
Quantum Control of Molecular Gas Hydrodynamics
Sina Zahedpour, Jared Wahlstrand, Howard Milchberg
We demonstrate that strong impulsive gas heating or heating suppression at standard temperature and pressure can occur from coherent rotational excitation or de-excitation of molec…
Direct measurement of the acoustic waves generated by femtosecond filaments in air
J. K. Wahlstrand, N. Jhajj, E. W. Rosenthal +2
We present direct measurements of the gas acoustic dynamics following interaction of spatial single- and multi-mode 50 fs, 800 nm pulses in air at 10 Hz and 1 kHz repetition rates.…
Demonstration of long-lived high power optical waveguides in air
N. Jhajj, E. W. Rosenthal, R. Birnbaum +2
We demonstrate that femtosecond filaments can set up an extended and robust thermal waveguide structure in air with a lifetime of several milliseconds, making possible the very lon…
Effect of two-beam coupling in strong-field optical pump-probe experiments
J. K. Wahlstrand, J. H. Odhner, E. T. McCole +4
Nonlinear optics experiments measuring phase shifts induced in a weak probe pulse by a strong pump pulse must account for coherent effects that only occur when the pump and probe p…
Terahertz generation by optical rectification in uniaxial birefringent crystals
J. D. Rowley, J. K. Wahlstrand, K. T. Zawilski +3
The angular dependence of terahertz (THz) emission from birefringent crystals can differ significantly from that of cubic crystals. Here we consider optical rectification in uniaxi…
Effect of a plasma grating on pump-probe experiments near the ionization threshold in gases
J. K. Wahlstrand, H. M. Milchberg
Calculations are performed of the phase shift caused by the spatial modulation in the plasma density due to interference between a strong pump pulse and a weak probe pulse. It is s…
Optical nonlinearity in Ar and N near the ionization threshold
J. K. Wahlstrand, Y. -H. Cheng, Y. -H. Chen +1
We directly measure the nonlinear optical response in argon and nitrogen in a thin gas target to laser intensities near the ionization threshold. No instantaneous negative nonlinea…