Virtual Journal of Laser

Joshua R. Freeman, Owen P. Marshall, Harvey E. Beere, David A. Ritchie
Electrically switchable emission in a terahertz quantum cascade laser is demonstrated. Two active region designs are incorporated into the same waveguide, forming a heterogeneous cascade that lases at frequencies around 2.6 THz and 3.0 THz. We find that the position of the active regions within the ... [Opt. Express 16, 19830-19835 (2008)]

Naokatsu Yamamoto, Hideyuki Sotobayashi, Kouichi Akahane, Masahiro Tsuchiya, Keijiro Takashima, Hiroyuki Yokoyama
To open up a 1-μm waveband for photonic transport systems, we developed a hybrid and harmonically mode-locked semiconductor laser (MLL) that can transmit return-to-zero (RZ) optical signals at data rates on the order of gigabits per second. A single-mode hole-assisted fiber (HAF) was also ... [Opt. Express 16, 19836-19843 (2008)]

Ki-Nam Joo, Yunseok Kim, Seung-Woo Kim
We describe a combined interferometric scheme that enables absolute distance measurements using a femtosecond pulse laser. This method is combined with synthetic wavelength interferometry (SWI), time of flight (TOF) and spectrally-resolved interferometry (SRI) using the optical comb of femtosecond ... [Opt. Express 16, 19799-19806 (2008)]

Carles Serrat, Jens Biegert
We investigate a method for complete population inversion in three level systems through π-pulse bichromatic two-photon coherent excitation and study the dependence on the chirp of the laser pulses. We observe that the population inversion does not monotonously decrease with increasing the ... [Opt. Express 16, 19667-19673 (2008)]

Z. B. Wang, Wei Guo, A. Pena, D. J. Whitehead, B. S. Luk'yanchuk, Lin. Li, Z. Liu, Y. Zhou, M. H. Hong
Based on medium-tuned optical field enhancement effect around a self-assembled particle-lens array (PLA) irradiated with a femtosecond (fs) laser source, we demonstrated that high-precision periodical array of micro/nano-structures can be readily fabricated on glass surface or inside glass in ... [Opt. Express 16, 19706-19711 (2008)]

Qiang Zhang, Carsten Langrock, M. M. Fejer, Yoshihisa Yamamoto
A periodically poled lithium niobate (PPLN) waveguide-based single-pixel up-conversion infrared spectrometer was demonstrated. Sum-frequency generation between a 1.5-μm-band scanning pump laser and a 1.3-μm-band signal generated visible radiation which was detected by a silicon ... [Opt. Express 16, 19557-19561 (2008)]

Michael Schultz, Heike Karow, Oliver Prochnow, Dieter Wandt, Uwe Morgner, Dietmar Kracht
We report on an all-fiber femtosecond ytterbium laser without dispersion compensation consisting of all-normal dispersion fibers. Modelocking was achieved by nonlinear polarization evolution in combination with additional amplitude modulation generated by a fiber-based spectral filter. The ... [Opt. Express 16, 19562-19567 (2008)]

Y. Bellouard, E. Barthel, A. A. Said, M. Dugan, P. Bado
Low energy femtosecond laser pulses locally increase the
refractive index and the hydro-fluoric acid etching rate of fused silica. These
phenomena form the basis of a direct-write method to fabricate integrated
glass devices that are of particular interest for optofluidics and
optomechanical ... [Opt. Express 16, 19520-19534 (2008)]

V. M. Menon, M. Luberto, N. V. Valappil, S. Chatterjee
We report the realization of a mechanically flexible microcavity
laser emitting at 657 nm using spin coating. These optically pumped vertical
cavity surface emitting lasers use InGaP colloidal quantum dots as the
active medium and alternating polymer layers of different refractive indices
as ... [Opt. Express 16, 19535-19540 (2008)]

Emilie Herault, Mickaël Lelek, François Balembois, Patrick Georges
A nonlinear cavity dumping process is applied for the first time to generate kW peak power pulses at 491 nm. The system is based on efficient sum-frequency mixing of 1063 nm and 912 nm radiations in a BiBO nonlinear crystal placed inside a Nd:GdVO4 laser oscillator with a high finesse cavity at 912 ... [Opt. Express 16, 19419-19426 (2008)]