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991.
992.
Xiong-jun Liu Xin Liu Leong-Chuan Kwek Choo Hiap Oh 《Frontiers of Physics in China》2008,3(2):113-125
Optical orbital angular-momentum (OAM) has more complex mechanics than the spin degree of photons, and may have a broad range
of application. Manipulating atomic states via OAM has become an interesting topic. In this paper, we first review the general
theory of generating adiabatic gauge field in ultracold atomic systems by coupling atoms to external optical fields with OAM,
and point out the applications of the generated adiabatic gauge field. Then, we review our work in this field, including the
generation of macroscopic superposition of vortex-antivortex states and spin Hall effect (SHE) in cold atoms.
相似文献
993.
994.
Cold atoms bouncing on a modulated atomic mirror exhibit dynamic localization and acceleration subject to modulated strength.
We explain the characteristics of acceleration using accelerated mapping and define control parameters. We show that the effective
Planck’s constant plays a vital role in limiting overall linear growth of accelerated atoms with time. For large values of
the effective Planck’s constant, the atomic quantum accelerated is seized if the localization window overlaps the accelerated
window. 相似文献
995.
996.
It is natural to define a Coxeter transformation in quantum groups by the product of Lusztig's symmetries in some order. In this note, we show that the Ringel–Hall algebra approach enables us to determine the behavior of its action in case of finite type. 相似文献
997.
998.
In the proposed accelerator driven systems (ADS) the possible use of several milliamperes of protons of about 1 GeV incident
on high mass targets like the molten lead-bismuth eutectic is anticipated to pose radiological problems that have so far not
been encountered by the radiation protection community. Spallation reaction products like high energy gammas, neutrons, muons,
pions and several radiotoxic nuclides including Po-210 complicate the situation. In the present paper, we discuss radiation
safety measures like bulk shielding, containment of radiation leakage through ducts and penetration and induced activity in
the structure to protect radiation workers as well as estimation of sky-shine, soil and ground water activation, release of
toxic gases to the environment to protect public as per the stipulations of the regulatory authorities. We recommend the application
of the probabilistic safety analysis technique by assessing the probability and criticality of different hazard-initiating
events using HAZOP and FMECA.
相似文献
999.
P. Ganguly 《Journal of Chemical Sciences》2001,113(5-6):415-425
The prominent “1/3” effect observed in the Hall effect plateaus of two-dimensional electron gas (2DEG) systems has been postulated
to indicating 1/3 fractional charge quasiparticle excitations arising from electron-electron interactions. Tunneling shot-noise
experiments on 2DEF exhibiting fractional quantum Hall effect (FQHE) shows evidence for tunnelling of particles with eand
e/3 charges for a constant band mass. A “1/3” effect in the hydrogen molecule is seen in as much as its internuclear distance,d
H-H
= D− + D+, with |D+/D−| = 1/3. This is examined in terms of electron-electron interactions involving electron-and hole quasiparticles, (e-)and(h
+
), equivalent to those observed in FQHE shot -noise experiments. The(e/m) ratio of the (e−) and(h
+
) quasiparticles is kept at 1: −3. Instead of a 2DEG, these particles are treated as being in flat Bohr orbits. A treatment
in the language of charge-flux tube composites for the hydrogen atom as well as the hydrogen molecule is attempted. Such treatment
gives important insights into changes in chemical potential and bond energy on crossing a phase boundary during the atom-bond
transition as well as on models for FQHE itself. 相似文献
1000.
A. M. Kozodaev N. D. Gavrilin M. M. Igumnov V. N. Konev N. V. Lazarev A. M. Raskopin V. V. Seliverstov O. V. Shvedov E. B. Volkov 《Pramana》2007,68(2):243-255
In this report, the purpose and status of the currently constructed ITEP experimental accelerator driven system (XADS) are
discussed. This hybrid electro-nuclear facility of moderate power integrates the pulse proton linac (36 MeV, 0.5 mA) and heavy
water sub-critical blanket assembly (heat power of 100 kW). Most parts of the equipment units are ordered for industrial manufacturing
and some are under development. The facility is supposed to be used for investigations of a wide range of problems concerning
both the target-blanket assembly and the accelerator-driver and at the same time explore the dynamical processes arising during
their combined operation. Some other applications of the proton beam and neutron source are also discussed. It is possible
in future to increase the current and energy of proton or heavy ion beam.
相似文献