1-GHz repetition-rate frequency-modulation mode-locked neodymium lasers at 13 μm

1991 ◽  
Vol 16 (14) ◽  
pp. 1101 ◽  
Author(s):  
Feng Zhou ◽  
G. P. A. Malcolm ◽  
A. I. Ferguson
2005 ◽  
Vol 83 (10) ◽  
pp. 1306-1313 ◽  
Author(s):  
P Galeotti ◽  
R Sacchi ◽  
M Fasola ◽  
D Pellitteri Rosa ◽  
M Marchesi ◽  
...  

Like other terrestrial tortoises, the courtship behaviour of Hermann's tortoises (Testudo hermanni Gmelin, 1789) is based on a multiple signalling system that involves visual, olfactory, tactile, and acoustic signals. In this study, we analysed relationships between male morphology, hematological profile, courtship intensity, vocalizations, and mounting success in Hermann's tortoises breeding in semi-natural enclosures to investigate the effects of male condition on signals exhibited during courtship and on their mounting success. Results showed that mounting success of Hermann's tortoise males was positively affected by the number of sexual interactions/h, number of bites given to the female during interactions, and by call rate and frequency-modulation range. Call rate, frequency-modulation range, and number of sexual interaction/h increased with hematocrit value, while number of bites given to females decreased with leukocyte concentration. In conclusion, courtship signals exhibited by Hermann's tortoise males, including vocalizations, reliably reveal different components of male condition, and females may use these multiple traits to choose high-quality partners. This is the first study documenting the condition-dependent nature of tortoise courting signals and their effect on male mounting success.


Author(s):  
Gaurav Chawla ◽  
Santiago D. Solares

The ability of atomic force microscopy (AFM) to acquire tip-sample interaction force curves has allowed researchers to understand the mechanical behavior of numerous materials at the nanoscale. However, AFM force spectroscopy with the most commonly used techniques can be a slow process for non-uniform samples, as it often requires the measurement to be performed at one fixed surface point at a time. In this paper we present two dynamic AFM based spectroscopy methods, one requiring operation in single-frequency-modulation mode and another using dual-frequency-modulation, which could allow a more rapid acquisition of topography and tip-sample interaction force curves. Numerical simulation results are provided along with discussions on the benefits and limitations of both.


2012 ◽  
Vol 3 ◽  
pp. 336-344 ◽  
Author(s):  
Miriam Jaafar ◽  
David Martínez-Martín ◽  
Mariano Cuenca ◽  
John Melcher ◽  
Arvind Raman ◽  
...  

We introduce drive-amplitude-modulation atomic force microscopy as a dynamic mode with outstanding performance in all environments from vacuum to liquids. As with frequency modulation, the new mode follows a feedback scheme with two nested loops: The first keeps the cantilever oscillation amplitude constant by regulating the driving force, and the second uses the driving force as the feedback variable for topography. Additionally, a phase-locked loop can be used as a parallel feedback allowing separation of the conservative and nonconservative interactions. We describe the basis of this mode and present some examples of its performance in three different environments. Drive-amplutide modulation is a very stable, intuitive and easy to use mode that is free of the feedback instability associated with the noncontact-to-contact transition that occurs in the frequency-modulation mode.


2006 ◽  
Vol 31 (11) ◽  
pp. 1627 ◽  
Author(s):  
Wei-Wei Hsiang ◽  
Chien-Yu Lin ◽  
Yinchieh Lai

MRS Advances ◽  
2016 ◽  
Vol 1 (25) ◽  
pp. 1853-1858 ◽  
Author(s):  
Sergei Magonov ◽  
Sergey Belikov ◽  
John Alexander ◽  
Marko Surtchev

ABSTRACTThe set of oscillatory resonance AFM modes is expanded with frequency modulation mode and frequency imaging in amplitude modulation mode. The backgrounds of these modes are discussed and their capabilities are compared on the practical examples. The data show how these techniques complement the amplitude modulation with phase imaging. The frequency imaging enhances the compositional mapping of heterogeneous samples. Frequency modulation mode provides a superior capability in imaging at low tip-sample forces.


2014 ◽  
Vol 23 (02) ◽  
pp. 1450016 ◽  
Author(s):  
Guanyu Liu ◽  
Zhiqiang Lv ◽  
Zibo Gong ◽  
Kebin Shi

We report on frequency doubling of 1.55-μm fiber oscillator-amplifier laser with conversion efficiency of 27% by using off-the-shelf nonlinear crystal. The system generates 135-femto-second (fs) pulses with average power of 110 mW at 80 MHz repetition rate. Frequency doubling efficiency as a function of pulse pre-chirp in front of a single mode erbium fiber amplifier was investigated.


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