Results 201 to 210 of about 58,001 (244)

Theory of photoelectric detection of light fluctuations

Proceedings of the Physical Society, 1964
The basic formulae governing the fluctuations of counts registered by photoelectric detectors in an optical field are derived. The treatment, which has its origin in Purcell's explanation of the Hanbury Brown-Twiss effect, is shown to apply to any quasi-monochromatic light, whether stationary or not, and whether of thermal origin or not.
L. MANDEL, E.C.G. SUDARSHAN, E. WOLF
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Photosynthesis in Fluctuating Light Environments

2006
The light environment in plant canopies is characterized by rapid fluctuations in photon flux density (PFD) because of the occurrence of sunflecks. These sunflecks can contribute most of the PFD available for photosynthesis and thus the mechanisms that control their utilization can have a significant impact on the carbon gain within canopies or in ...
Robert W. Pearcy, John P. Krall, Gretchen F. Sassenrath-Cole   +2 more
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Photosynthesis in fluctuating light

2023
Light is the essential energy source for plants to drive photosynthesis. In nature, light availability is highly variable and often fluctuates on very short time scales. As a result, plants developed mechanisms to cope with these fluctuations. Understanding how to improve light use efficiency in natural fluctuating light (FL) conditions is a major ...
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Light fluctuations in the laser

International Laser Science Conference, 1986
When the working point of a laser is taken through its threshold of oscillation, the optical field undergoes an order-disorder type of phase transition, which is manifest in the statistics of the emitted light photons, and has been studied experimentally by photoelectric counting and correlation measurements. In a single-mode laser the phase transition
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Molecular excitation processes by fluctuating light

Chemical Physics Letters, 1979
Abstract The “reduced” model theory is extended in such a way as to allow a quantitative study of excitation processes by pulses having a width greater than their uncertainty-limited value.
Maurizio Benfatto, Paolo Grigolini
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Coherence and Fluctuations in Light Beams

American Journal of Physics, 1964
A quasithermal, quasmonochromatic lamp is described which serves as a highly degenerate light source with adjustable coherence time between 10−5 sec and 1 sec. This lamp is used for several demonstration experiments concerning the relations between coherence and fluctuations: The intensity interferometer of Hanbury Brown and Twiss is applied to measure
W. Martienssen, E. Spiller
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V Fluctuations of Light Beams

1963
Publisher Summary This chapter describes the fluctuations of light beams. Like other fluctuation problems concerned with departures from equilibrium, radiation fluctuations in an enclosure can be treated by the methods of statistical mechanics. The fluctuations of the counts recorded by a photo-detector illuminated by Gaussian light depart from ...
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Frequency dependence of laser light fluctuations

Physical Review A, 1983
The equations of motion for an inhomogeneously broadened laser operating off resonance in the neighborhood of threshold are solved. It is shown that the effects of detuning cannot be described just by a frequency-dependent laser pump parameter, but that the laser characteristics are modified in other ways also.
Surendra Singh, S. Friberg, L. Mandel
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Optical fluctuations of light-emitting diodes

IEEE Journal of Quantum Electronics, 1972
Intensity fluctuations of GaAs light-emitting diodes (LED) have been measured at 25°C ambient temperature in the frequency range of 25 Hz to 20 kHz. A dependence of optical fluctuations at low frequencies on diode current and also on the direction of emitted radiation has been found.
J. Conti, M. Strutt
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Squeezed Light and Its Photocurrent Fluctuations

1996
In this paper. we propose a general theory that enables us to calculate the photocurrent noise spectrum of various squeezed light. Considering the coupling between the light and the detector, the photocurrents can be described by a set of stochastic differential equations.
Hsin-Fei Meng, Chih-Ming Lai
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