Showing papers by "Er'el Granot published in 2006"
TL;DR: In this article, the spectral ballistic imaging technique was used to measure the impulse response of a Fabry-Perot etalon with less than 0.2 ps temporal resolution and the results show excellent agreement with the theoretical predictions and negligible noise.
Abstract: We use the spectral ballistic imaging technique to measure the impulse response of a Fabry–Perot etalon with less than 0.2 ps temporal resolution. The results show excellent agreement with the theoretical predictions and negligible noise. Comparison to the Kramers–Kronig method along with its limitations is also presented.
9 citations
TL;DR: It is shown that by averaging the temporal optical field response of a diffusive medium (as opposed to the optical intensity response) the signal-to-noise ratio of the object's reflection can be improved considerably.
Abstract: We measure the sub-picosecond optical impulse response of a system consisting of a varying 1D diffusive medium and a stationary hidden object. It is shown that by averaging the temporal optical field response of a diffusive medium (as opposed to the optical intensity response) the signal-to-noise ratio of the object’s reflection can be improved considerably. The Spectral-Ballistic-Imaging technique is used to reconstruct the optical-field impulse response with a 200fs temporal resolution.
7 citations
TL;DR: In this article, it was shown that the cross section of a point scatterer exhibits a resonance dependence on the scatterers strength, and in the singular 2D case it gets its maximum value for an infinitely weak strength.
Abstract: It is well known that in 1D the cross section of a point scatterer increases along with the scatterer's strength (potential). In this paper we show that this is an exceptional case, and for lower or higher number of dimensions, i.e., 0 d 1 and 1 d ⩽ 2 (d is the dimensions number), the cross section does not increase monotonically with the scatterer's strength. In fact, the cross section exhibits a resonance dependence on the scatterer's strength, and in the singular 2D case it gets its maximum value for an infinitely weak strength. We use this fact to show that two totally different generalized function can describe exactly the same physical entity (the same scatterer).
6 citations
TL;DR: In this paper, the short-time dynamics of a delta-function potential barrier on an initially confined wave packet were investigated, and it was shown that at short times the probability density of the first particles that passed through the barrier is unaffected by it.
Abstract: We investigate the short-time dynamics of a delta-function potential barrier on an initially confined wave packet. There are mainly two conclusions: (A) At short times the probability density of the first particles that passed through the barrier is unaffected by it. (B) When the barrier is absorptive (i.e., its potential is imaginary) it affects the transmitted wave function at shorter times than a real potential barrier. Therefore, it is possible to distinguish between an imaginary and a real potential barrier by measuring its effect at short times only on the transmitting wave function.
6 citations
TL;DR: In this paper, the temporal response of a stimulated Brillouin scattering generator to an harmonically modulated pump beam in a 2.1-km optical fiber was analyzed both theoretically and experimentally, and it was shown that at certain frequencies f min ≅ f c G m (where m is an integer number and f c g ≅ c ( 1 - G - 1 ) / 2 nL are frequencies which depends mainly on the fiber's length L but also on the beam's intensity via G ) the first harmonic of the generated Stokes beam is relatively suppressed but never van
6 citations
TL;DR: The conditions for quasi-phase matching of the interacting intensity waves are developed and it is shown that a periodic nonlinearity can be utilized to eliminate the dephasing between them.
Abstract: The evolution of modulated light in a nonlinear medium, when described in terms of intensity waves, depends critically on a phase-matching condition for the intensity waves. We formally develop the conditions for quasi-phase matching of the interacting intensity waves and show that a periodic nonlinearity can be utilized to eliminate the dephasing between them. This is verified using stimulated Brillouin scattering with a periodically nonlinear optical fiber that has a period length equal to one-half of the (modulation) wavelength of the intensity waves.
4 citations
TL;DR: In this article, the authors present an experimental and theoretical study of a highly robust wavelength converter at 10Gbit/s that is based on a narrow bandstop Brillouin filter.
Abstract: We present an experimental and theoretical study of a highly robust wavelength converter at 10Gbit/s that is based on a narrow bandstop Brillouin filter. The wavelength conversion takes place in a semiconductor optical amplifier in a cross-gain-phase process, which operates in a weak-modulation mode. The signal then undergoes a carrier reduction by a spectrally narrow bandstop filter. Since we use a Brillouin grating as the narrow filter, the signal is distorted owing to the filter's finite spectral width (~20 MHz). To overcome this problem, we use a relatively slow electronic mechanism to effectively narrow the filter's spectral width and to improve its signal-to-noise ratio. We elaborate on this electronic mechanism by developing the underlying theory and showing how it is implemented in practice. Although we focus on an application for wavelength conversion, this technology can be implemented in many other cases in which an effective narrowing of a bandstop filter is required.
3 citations
TL;DR: In this article, an all-optical signal regenerator (AOSR) is proposed, which is based on a semiconductor optical amplifier (SOA), which is incorporated in an asymmetric Sagnac loop (ASL).
1 citations