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Patent

Method and arrangement for generating binary sequences of random numbers

TLDR
In this article, a beam splitter is used to select the photons in the beam path of a low-power light source and then the photons are split up by the beams splitters (ST1, ST2) arranged one after the other in the path of the light source.
Abstract
The aim of the invention is to provide an inexpensive method and an arrangement for generating binary sequences of random numbers. The invention should also be easy to integrate onto a chip card. The inventive method is based on the principle of the random path selection of photons in a beam splitter and the generation of a random numbers by means of two detectors (D10; D21) situated downstream of a beam splitter (ST2). According to the invention, a low-power light source (L) is used to produce the photons and an additional beam splitter (ST1) is arranged upstream of the original beam splitter (ST2). The photons emitted by the light source (L) for a set measuring period are split up by the beams splitters (ST1; ST2) arranged one after the other in the beam path of the light source (L). The random sequence is generated when the splitting up of the photons is matched with a predetermined photon model. The invention provides an inexpensive random-check generator which is easy to integrate onto a chip card, especially because of the light source (L) used.

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Citations
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References
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Journal ArticleDOI

Quantum Random-number Generation and Key Sharing

TL;DR: A simple approach to generating the random measurement bases used in quantum cryptography systems which exploits random partition at a beam splitter, reducing system complexity and losses.
Patent

Interferometric quantum cryptographic key distribution system

TL;DR: In this article, an apparatus and method for distributing cryptographic key information was described incorporating a quantum channel for conveying dim and reference light pulses, a timing channel, a source of coherent light pulses and beamsplitters, a random number generator, a phase modulator and a memory for recording the phase of transmitted dim light pulses.
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Time resolved optical array detectors and CCD cameras for frequency domain fluorometry and/or phosphorimetry

TL;DR: In this article, a cross-correlation frequency domain fluorometry-phosphorimetry (CDF) system is described, where a signal is provided coherent with the amplitude modulated electromagnetic radiation signals, at a second frequency which is different from the first frequency.
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Secure communications with low-orbit spacecraft using quantum cryptography

TL;DR: In this article, a beam-plitter randomly directs the preceding bright pulses and the polarized delayed attenuated pulses onto longer and shorter paths, both terminating in a beamsplitter which directs a first portion of the polarized delay attenuated signals to a first detector, and a second portion to a second detector.
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Positive-operator-valued-measure receiver for quantum cryptography

TL;DR: In this article, an all-optical realization of the POVM is presented, which includes a Wollaston prism, a mirror, two beam splitters, a polarization rotator, and three photodetectors.