328 research outputs found
ANALYSIS OF PUBLIC UNDERSTANDING OF NEW TECHNOLOGIES AND INNOVATIVE DEVELOPMENT IN UKRAINE: CURRENT PROBLEMS AND PERSPECTIVES
As Ukraine proclaimed the model of innovative economic development in 2001
and chose `the development of new and resources-economy technologies in the
industry and the agricultural complex´ as one of the priority directions,
this topic is of great interest for our society. Development of genetic
engineering, biotechnology and their safe application are the most urgent
questions.
There are some biotechnological risks, which are highly discussed in mass
media. They are:
- transfer of artificial genetic constructions to genotype of existing
organisms and appearance of more viable unhealthy organisms which can
displace other organisms;
- appearance of new albumen and biologically active substances which are
harmful for people and animals. These problems are known as `biosafety´.
Scientists of the world develop theoretical basis of `biosafety´, create
legislative base which could provide health and environment protection.
Our Ukrainian scientists have good results in biotechnology. There are
some examples: microbe super synthesis of some important albumen; creation
of bio-sensory systems for medicine and ecology; creation of new transgene
plants.
These investigations are biologically not so harmful as they are not used in
practice yet. Another danger exists. Foreign biotechnological companies are
interested in the promotion of their products at Ukrainian market. These
products are very often not checked. Now in Ukraine transgenic products are
being tested although it contradicts to our legislation. Thus, genetically
modified potatoes are tested in Ukraine (resistant to Colorado beetle,
MONSANTO Company), as well as corn (resistant to insects, NOVARTIS Company),
sugar beet, etc.
Committee for safety questions was established at the Ministry of Science and
Technology. Some conditions of ecological safety are included in the laws
of Ukraine, but some standard legislative acts contradict to the Ukrainian
legislation. Scientists of Ukraine proclaimed the necessity of
intensification of the state control on safety during works in genetic
engineering and on entry of unaudited products in Ukraine. Moreover, they
emphasized the necessity of cooperation with European Community in
terms of biosafety.
So, conferences, symposia on legislative regulation are held. Not only
specialists take part in such discussions but also mass media, Internet
visitors discuss them on-line.
The raising of the interest in biotechnology and
ecological safety on the part of society is also necessary to mention
All-atomic source of squeezed vacuum with full pulse-shape control
We report on the generation of pulses of a low-frequency squeezed vacuum with
noise suppression >2 dB below the standard quantum limit in a hot resonant 87
Rb vapor with polarization self-rotation. We demonstrate the possibility to
precisely control the temporal profile of the squeezed noise quadrature by
applying a calibrated longitudinal magnetic field, without degrading the
maximum amount of squeezing
Light storage in an optically thick atomic ensemble under conditions of electromagnetically induced transparency and four-wave mixing
We study the modification of a traditional electromagnetically induced
transparency (EIT) stored light technique that includes both EIT and four-wave
mixing (FWM) in an ensemble of hot Rb atoms. The standard treatment of light
storage involves the coherent and reversible mapping of one photonic mode onto
a collective spin coherence. It has been shown that unwanted, competing
processes such as four-wave mixing are enhanced by EIT and can significantly
modify the signal optical pulse propagation. We present theoretical and
experimental evidence to indicate that while a Stokes field is indeed detected
upon retrieval of the signal field, any information originally encoded in a
seeded Stokes field is not independently preserved during the storage process.
We present a simple model that describes the propagation dynamics of the fields
and the impact of FWM on the spin wave.Comment: 13 pages, 10 figure
Improving Sensitivity of an Amplitude-Modulated Magneto-Optical Atomic Magnetometer using Squeezed Light
We experimentally demonstrate that a squeezed probe optical field can improve
the sensitivity of the magnetic field measurements based on nonlinear
magneto-optical rotation (NMOR) with an amplitude-modulated pump when compared
to a coherent probe field under identical conditions. To realize an all-atomic
magnetometer prototype, we utilize a nonlinear atomic interaction, known as
polarization self-rotation(PSR), to produce a squeezed probe field. An
independent pump field, amplitude-modulated at the Larmor frequency of the bias
magnetic field, allows us to extend the range of most sensitive NMOR
measurements to sub-Gauss magnetic fields. While the overall sensitivity of the
magnetometer is rather low (, we clearly
observe a sensitivity improvement when the squeezed probe is used. Our
observations confirm the recently reported quantum enhancement in a modulated
atomic magnetometer arXiv:2108.01519 [quant-ph]
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