557 research outputs found
Giant magnetothermal conductivity and magnetostriction effect in charge ordered NdNaMnO compound
We present results on resistivity (), magnetization (), thermal
conductivity (), magnetostriction () and
specific heat () of charge-orbital ordered antiferromagnetic
NdNaMnO compound. Magnetic field-induced
antiferromagnetic/charge-orbital ordered insulating to ferromagnetic metallic
transition leads to giant magnetothermal conductivity and magnetostriction
effect. The low-temperature irreversibility behavior in , ,
and due to field cycling together with striking
similarity among the field and temperature dependence of these parameters
manifest the presence of strong and complex spin-charge-lattice coupling in
this compound. The giant magnetothermal conductivity is attributed mainly to
the suppression of phonon scattering due to the destabilization of spin
fluctuations and static/dynamic Jahn-Teller distortion by the application of
magnetic field.Comment: 4 Pages, 4 Figure
Realization of a twin beam source based on four-wave mixing in Cesium
Four-wave mixing (4WM) is a known source of intense non-classical twin beams.
It can be generated when an intense laser beam (the pump) and a weak laser beam
(the seed) overlap in a medium (here cesium vapor), with
frequencies close to resonance with atomic transitions. The twin beams
generated by 4WM have frequencies naturally close to atomic transitions, and
can be intense (gain ) even in the CW pump regime, which is not the case
for PDC phenomenon in non-linear crystals. So, 4WM is well suited
for atom-light interaction and atom-based quantum protocols. Here we present
the first realization of a source of 4-wave mixing exploiting line of
Cesium atoms.Comment: 10 pages, 10 figure
Two-mode squeezed vacuum and squeezed light in correlated interferometry
We study in detail a system of two interferometers aimed to the detection of
extremely faint phase-fluctuations. This system can represent a breakthrough
for detecting a faint correlated signal that would remain otherwise
undetectable even using the most sensitive individual interferometric devices,
that are limited by the shot noise. If the two interferometers experience
identical phase-fluctuations, like the ones introduced by the so called
"holographic noise", this signal should emerge if their output signals are
correlated, while the fluctuations due to shot noise and other independent
contributions will vanish. We show how the injecting quantum light in the free
ports of the interferometers can reduce the photon noise of the system beyond
the shot-noise, enhancing the resolution in the phase-correlation estimation.
We analyze both the use of two-mode squeezed vacuum or twin-beam state (TWB)
and of two independent squeezing states. Our results basically confirms the
benefit of using squeezed beams together with strong coherent beams in
interferometry, even in this correlated case. However, mainly we concentrate on
the possible use of TWB, discovering interesting and probably unexplored areas
of application of bipartite entanglement and in particular the possibility of
reaching in principle surprising uncertainty reduction
High Order Asymptotic Preserving and Classical Semi-implicit RK Schemes for the Euler-Poisson System in the Quasineutral Limit
In this paper, the design and analysis of high order accurate IMEX finite
volume schemes for the compressible Euler-Poisson (EP) equations in the
quasineutral limit is presented. As the quasineutral limit is singular for the
governing equations, the time discretisation is tantamount to achieving an
accurate numerical method. To this end, the EP system is viewed as a
differential algebraic equation system (DAEs) via the method of lines. As a
consequence of this vantage point, high order linearly semi-implicit (SI) time
discretisation are realised by employing a novel combination of the direct
approach used for implicit discretisation of DAEs and, two different classes of
IMEX-RK schemes: the additive and the multiplicative. For both the time
discretisation strategies, in order to account for rapid plasma oscillations in
quasineutral regimes, the nonlinear Euler fluxes are split into two different
combinations of stiff and non-stiff components. The high order scheme resulting
from the additive approach is designated as a classical scheme while the one
generated by the multiplicative approach possesses the asymptotic preserving
(AP) property. Time discretisations for the classical and the AP schemes are
performed by standard IMEX-RK and SI-IMEX-RK methods, respectively so that the
stiff terms are treated implicitly and the non-stiff ones explicitly. In order
to discretise in space a Rusanov-type central flux is used for the non-stiff
part, and simple central differencing for the stiff part. AP property is also
established for the space-time fully-discrete scheme obtained using the
multiplicative approach. Results of numerical experiments are presented, which
confirm that the high order schemes based on the SI-IMEX-RK time discretisation
achieve uniform second order convergence with respect to the Debye length and
are AP in the quasineutral limit
A New Approach to Power System Protection using Time-frequency Analysis and Pattern Recognition
The fault diagnosis of Electric Power System is a process of discriminating the faulted system elements by protective relays and subsequent tripping by circuit breakers. Specially, as soon as some serious faults occur on a power system, a lot of alarm information is transmitted to the control center. Under such situation, the operators are required to judge the cause, location, and the system elements with faults rapidly and accurately. Thus, good fault diagnosis methods can provide accurate and effective diagnostic information to dispatch operators and help them take necessary measures in fault situation so as to guarantee the secure and stable operation of the Electric power system. This thesis reports various techniques used for detection, classification and localization of faults on the high voltage transmission line. The distance protection scheme for transmission line is employed for various power networks such as single-circuit line, double-circuit line, and lines having FACTS ..
Review on Sneha Kalpana with special reference to Narasimha Ghrita
Medicated ghee that is Ghrita Kalpana is a unique Ayurvedic preparation widely used by the physicians for various purposes. Narsimha Ghrita - a Sneha Kalpana is a famous formulation, indicated in Khalitya, Palitya as well used as Vajikarana and Rasayana. Ashtanga Hridaya and Gada Nigraha are the two references available in the classics for this formulation. All the market available samples are as per the reference of Ashtanga Hridaya but in the form of Lehya rather the Ghrita form. Hence the present article is an attempt to review the different references of Narasimha Ghrita
Critical analysis of Haridra Khanda - An Ayurvedic Formulation
Haridra Khanda is unique classical formulation indicated in Udarda, shitapitta, kotha (urticarial rashes) this product is available in the market and widely used by Ayurvedic physicians. Here, an attempt was done for conducting comparative pharmaceutical study of Haridra Khanda of different references by preparing it as mentioned in the classics. All 4 formulations are different by their ingredients and Anupana
Review article on Swarna Parpati with special reference to Aushadhi Gunadharma Shastra
In Ayurveda, Swarna (gold) Bhasma in different formulations has been administered to patients as a therapeutic agent for several clinical disorders including respiratory disorders, rheumatoid arthritis, diabetes mellitus and nervous system diseases. It is one of the metals which is even indicated since the birth. Parapati Kalpana is well known and successfully used preparations for the management of Grahani Roga. Swarna Parpati is one of the formulation of Ayurveda which comes under Parpati Kalpana. This article has reviewed Swarna Parpati from different classics with special reference to book Aushadhi Gundharma Shastra of Acharya Gune Shastri
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