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Now showing items 41-50 of 72
Electrical and optical characterization of conducting poly-3-methylthiophene film by THz time-domain spectroscopy
(AIP Publishing, 2002-12-17)
Using THz time-domain spectroscopy (THz-TDS), we have measured the absorption and dispersion of 7.5/(Ohm-cm) conducting poly-3-methylthiophene film from low frequencies up to 4 THz. From these measurements the complex ...
High-brightness terahertz beams characterized with an ultrafast detector
(AIP Publishing, 1989-07-24)
We have significantly improved the emission and detection of electromagnetic beams of single-cycle 0.5 THz pulses, through the use of new dipolar antenna structures. The frequency response was extended to well beyond the ...
Efficient generation of 380 fs pulses of THz radiation by ultrafast laser pulse excitation of a biased metal-semiconductor interface
(AIP Publishing, 1991-01-21)
We have demonstrated a new method of generating pulses of freely propagating THz electromagnetic radiation. The resulting 380 fs pulses are the shortest directly measured THz pulses in free space to date and are more ...
Nature of conduction in doped silicon
(American Physical Society, 1997-02-10)
Via ultrafast optoelectronic THz techniques, we are able to test alternative theories of conduction by precisely measuring the complex conductivity of doped silicon from low frequencies to frequencies higher than the plasma ...
Adiabatic following and slow optical pulse propagation in rubidium vapor
(American Physical Society, 1973-06)
Short pulses of narrow-line low-intensity dye-laser light nearly resonant with the Zeeman-split 2P1/2 esonance line (7948 A) of rubidium were observed to propagate through dilute rubidium vapor as slowly as (1/14)c. These ...
Self-focusing of light by potassium vapor
(American Physical Society, 1970-04-20)
Raman-shifted ruby-laser light on the high-frequency side of the 2P3/2 resonance line (7665 A) of potassium was self-focused by a dilute potassium gas.
Comment on the relationship between an exact two-photon solution and a two-photon vector model
(American Physical Society, 1977-04)
The exact pulse solution of Brewer and Hahn for optical two-photon transitions is shown to reduce in the adiabatic limit to the two-photon vector model used by Grischkowsky, Loy, and Liao. The connection between the two ...
Reduced conductivity in the terahertz skin-depth layer of metals
(AIP Publishing, 2007-03-23)
The terahertz conductivities of plates of Cu and Al were measured to remain the same at 295 and 77 K using waveguide terahertz time domain spectroscopy (THz-TDS). This result was true for a variety of commercial alloys and ...
Quasioptic dielectric tetrahertz cavity: Coupled through optical tunneling
(AIP Publishing, 2001-04-23)
We report the observation of the well defined oscillation of a picosecond tetrahertz (ps THz) pulse within a dielectric concentric cy1indrica1 cavity, which is coupled to an incoming focused beam of ps THz pulses by the ...
Behavior of electron-spin echoes and photon echoes in high fields
(American Physical Society, 1970-07-01)
The amplitude of the electron-spin or photon echo from an ensemble of isolated atoms (echo atoms) interacting with magnetic-nuclear neighbors is calculated as a function of the magnitude and the orientation of an applied ...