We report a novel optical spectral phase correlation scheme for coded ultrashort pulses based on the use of long periodically poled lithium niobate second harmonic generation waveguides. Second ...harmonic efficiency as high as 50%/pJ was obtained, which allowed us to demonstrate nonlinear detection of individual pulses at 0.25 pJ input energies over a 500-MHz detection bandwidth with > 50:1 signal-to-noise ratio. These results offer the possibility of sub-pJ real-time operation of such devices as nonlinear receivers in ultrashort-pulse optical code-division multiple-access (CDMA) networks
Quasi-matching (QPM) enables a variety of functions for ultrafast optics. Aperiodic QPM structures for tailoring wide mixing bandwidths for pulse shaping, broadband parametric amplification, and ...ultrasensitive pulse characterization in microstructured ferroelectrics and semiconductors are discussed.
We developed transmitter and receiver modules with Ti:PPLN waveguide operated as difference frequency generator to convert a signal (lambda s ~ 1550 nm) to the mid infrared (lambda i ~ 3800 nm) and ...back again.
We report a novel optical spectral phase correlation scheme for coded ultrashort pulses based on the use of long periodically poled lithium niobate second harmonic generation waveguides. Second ...harmonic efficiency as high as 50%/pJ was obtained, which allowed us to demonstrate nonlinear detection of individual pulses at 0.25 pJ input energies over a 500-MHz detection bandwidth with >50:1 signal-to-noise ratio. These results offer the possibility of sub-pJ real-time operation of such devices as nonlinear receivers in ultrashort-pulse optical code-division multiple-access (CDMA) networks
Phys. Rev. Lett. 127, 071101 2021 The sensitivity of current and planned gravitational wave interferometric
detectors is limited, in the most critical frequency region around 100 Hz, by a
combination ...of quantum noise and thermal noise. The latter is dominated by
Brownian noise: thermal motion originating from the elastic energy dissipation
in the dielectric coatings used in the interferometer mirrors. The energy
dissipation is a material property characterized by the mechanical loss angle.
We have identified mixtures of titanium dioxide (TiO$_2$) and germanium dioxide
(GeO$_2$) that show internal dissipations at a level of 1 $\times 10^{-4}$, low
enough to provide almost a factor of two improvement on the level of Brownian
noise with respect to the state-of-the-art materials. We show that by using a
mixture of 44% TiO$_2$ and 56% GeO$_2$ in the high refractive index layers of
the interferometer mirrors, it would be possible to achieve a thermal noise
level in line with the design requirements. These results are a crucial step
forward to produce the mirrors needed to meet the thermal noise requirements
for the planned upgrades of the Advanced LIGO and Virgo detectors.
High resolution polar Kerr effect (PKE) measurements were performed on La1.875Ba0.125Cuo4 single crystals revealing that a finite Kerr signal is measured below an onset temperature-T_K that coincides ...with charge ordering transition temperature T_{CO}. We further show that the sign of the Kerr signal cannot be trained with magnetic field, is found to be the same of opposite sides of the same crystal, and is odd with respect to strain in the diagonal direction of the unit cell. These observations are consistent with a chiral "gyrotropic" order above T_c for La1.875Ba0.125Cuo4; similarities to other cuprates suggest that it is a universal property in the pseudogap regime.
We experimentally demonstrate a tunable optical delay system that deploys dispersion, wavelength conversion In HNLF and multicasting in PPLN assisted with frequency comb lines pumping which offers ...discrete simultaneous access to the delayed signal.
Broadband continuum generation in GaAs Kuo, P.S.; Vodopyanov, K.L.; Simanovskii, D.M. ...
2006 Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference
Conference Proceeding
An ultrabroad infrared continuum can be produced using optical parametric generation (OPG) in quasi-phasematched GaAs. Spectra over an octave wide, spanning 4.5 to 10.7 microns, measured 20 dB down ...from the peak, have been observed.
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