1,504 research outputs found
Quantum dynamical correlations: Effective potential analytic continuation approach
We propose a new quantum dynamics method called the effective potential
analytic continuation (EPAC) to calculate the real time quantum correlation
functions at finite temperature. The method is based on the effective action
formalism which includes the standard effective potential. The basic notions of
the EPAC are presented for a one-dimensional double well system in comparison
with the centroid molecular dynamics (CMD) and the exact real time quantum
correlation function. It is shown that both the EPAC and the CMD well reproduce
the exact short time behavior, while at longer time their results deviate from
the exact one. The CMD correlation function damps rapidly with time because of
ensemble dephasing. The EPAC correlation function, however, can reproduce the
long time oscillation inherent in the quantum double well systems. It is also
shown that the EPAC correlation function can be improved toward the exact
correlation function by means of the higher order derivative expansion of the
effective action.Comment: RevTeX4, 20 pages, 6 eps figure
In-liquid plasma using microwave power for applications
[EN] The research of in-liquid plasma that uses microwave as an energy source can be
generated without depending on the electric conductivity of the solution, so it has wide
application. However, it is not practical because the microwave antenna (plasma electrode)
is deteriorated immediately. We were noticed that the microwave is pulsed to solve this
problem. In this study, its optimum conditions was investigated. The best parameters of
pulse microwave power was investigated using the generator (peak power ; 380 W, pulse
width ; 13.4 msec and pulse duty cycle ; 16.7 msec). Stable in-liquid plasma could be
generated in this conditions. This optimised system of in-liquid plasma tried to use
applications for wastewater treatment and gel synthesis. In first application (wastewater
treatment), tetrabromobisphenol A (TBBPA) was ionized and minerated by using in-liquid
plasma method for only 20 min, respectivily. In second one (gel synthesis), in-liquid plasma
can synthesize gel-synthesis without crosslinking agent and initiator. This new method could
synthesize gel of dimethyl polysiloxane (silicone) and polyvinilypirroridone (PVP) without
both crosslinking agent and initiator, it suggested that in-liquid plasma method is effective
as a green chemistry process.Sawada, S.; Horikoshi, S. (2019). In-liquid plasma using microwave power for applications. En AMPERE 2019. 17th International Conference on Microwave and High Frequency Heating. Editorial Universitat Politècnica de València. 59-66. https://doi.org/10.4995/AMPERE2019.2019.9815OCS596
Flow Equation for Supersymmetric Quantum Mechanics
We study supersymmetric quantum mechanics with the functional RG formulated
in terms of an exact and manifestly off-shell supersymmetric flow equation for
the effective action. We solve the flow equation nonperturbatively in a
systematic super-covariant derivative expansion and concentrate on systems with
unbroken supersymmetry. Already at next-to-leading order, the energy of the
first excited state for convex potentials is accurately determined within a 1%
error for a wide range of couplings including deeply nonperturbative regimes.Comment: 24 pages, 8 figures, references added, typos correcte
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