Significant enhancement in the direct amplitude modulation bandwidth of an SG-DBR laser has been demonstrated under strong injectionlocking conditions, where the wavelength detuning between the master and the free-running SG-DBR slave laser is varied from 28.58 to 13.6 nm. It is demonstrated that the relaxation resonance frequency of a strongly injection-locked SG-DBR laser increases from 1.05 ...

Traditional neutron tomography allows to reconstruct the attenuation cross section, a measure for the material distribution, at high spatial resolution and non-destructively. However, it does not state anything about the ordering structure of the atoms inside this material. Extending the setup with a second neutron imaging detector, diffracted neutrons from the ordered crystal lattice could be ...

A detailed model of diffraction of Gaussian beams on plane uniform volume Bragg gratings based on a Kogelnik’s theory of coupled waves is presented. The model describes transmitting and reflecting gratings and takes into account spectral width and angular divergence of diffracted beams. Exact formulas for angular and spectral selectivity are derived. Conditions for Bragg diffraction based on co...

The improvements of the optical single-mode fiber and the progress in semiconduetor technology, especially in the domain of diode lasers with emission wavelengths in the near IR (1.3/rni 1.6um) allow for the rapidly growing data transmission rates in optical communication Systems. High demands are made on the transmitters, the reeeivers and the transmitting media at data rates of several Gbit/s...

We have observed the pure rotational spectra of HBr isotopomers in their v = 0 and v = 1 states between 0.97 and 1.02 THz. i. e. the HBr .7 = 2—1 and the DBr .7 = 4 — 3 transitions, respectively. In the analysis, all presently available rotational transitions of all isotopomers have been fitted to a Dunham-type Hamiltonian to obtain the isotopically invariant parameters, including vibrational a...

We report the infrared operation of a bulk optical Bragg modulator based on electro-optically induced refractive index gratings in z-cut periodically poled lithium niobate. Efficiencies in the first order of 45% for 1064 nm e-polarized light and 30% for o-polarized light were achieved, with maximum on/off ratios of 15:1 and 9:1, respectively. Field-induced light scattering effects due to poling...

The emission properties of a porous silicon layer placed in an optical microcavity is investigated by photoluminescence and time resolved photoluminescence measurements. The microcavity is formed by an all porous silicon Fabry-Perot filter made by two distributed Bragg reflectors separated by a h or h/2 porous silicon layer. Our main findings are that the spontaneous emission spectrum is drasti...

We propose a new architecture for an optical fast frequency-hop code division multiple access (FFH-CDMA) system using tunable Bragg gratings. Previously proposed architectures called for a series of in-fiber Bragg gratings, each independently tunable with a piezo-electric device. We propose a system where the entire fiber of multiple Bragg gratings uses one piezo-electric device to tune to a pa...

Record high differential efficiency (53.2%) and full optical efficiency (48%) for a multimode diode-pumped Yb:KYW laser have been achieved. The characteristics of the laser and methods for improving its efficiency using a distributed Bragg reflector tapered diode laser (DBR TDL) are discussed.

An optically pumped mid-infrared edge-emitting laser is described, in which a Distributed Bragg Reflector grating partially occupies the surface, and provides spectral narrowing in a high power device. A quasi-continuous-wave power of 3 Watts is obtained at 3.6 µm that is contained within a spectral width of 7 nm.