اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدThermodynamics of second phase conductive filaments
35
0
0.0
(
0
)
اسأل ChatGPT حول البحث
ﻻ يوجد ملخص باللغة العربية
We present a theory of second phase conductive filaments in phase transformable systems; applications include threshold switches, phase change memory, and shunting in thin film structures. We show that the average filament parameters can be described thermodynamically. In agreement with the published data, the predicted filament current voltage characteristics exhibit negative differential resistance vanishing at high currents where the current density becomes a bulk material property. Our description is extendible to filament transients and allows for efficient numerical simulation.
قيم البحث
اقرأ أيضاً
We derive a generalization of the Second Law of Thermodynamics that uses Bayesian updates to explicitly incorporate the effects of a measurement of a system at some point in its evolution. By allowing an experimenters knowledge to be updated by the m
easurement process, this formulation resolves a tension between the fact that the entropy of a statistical system can sometimes fluctuate downward and the information-theoretic idea that knowledge of a stochastically-evolving system degrades over time. The Bayesian Second Law can be written as $Delta H(rho_m, rho) + langle mathcal{Q}rangle_{F|m}geq 0$, where $Delta H(rho_m, rho)$ is the change in the cross entropy between the original phase-space probability distribution $rho$ and the measurement-updated distribution $rho_m$, and $langle mathcal{Q}rangle_{F|m}$ is the expectation value of a generalized heat flow out of the system. We also derive refin
We have investigated thermal conductivity of graphene laminate films deposited on polyethylene terephthalate substrates. Two types of graphene laminate were studied - as deposited and compressed - in order to determine the physical parameters affecti
ng the heat conduction the most. The measurements were performed using the optothermal Raman technique and a set of suspended samples with the graphene laminate thickness from 9 to 44 micrometers. The thermal conductivity of graphene laminate was found to be in the range from 40 W/mK to 90 W/mK at room temperature. It was found unexpectedly that the average size and the alignment of graphene flakes are more important parameters defining the heat conduction than the mass density of the graphene laminate. The thermal conductivity scales up linearly with the average graphene flake size in both uncompressed and compressed laminates. The compressed laminates have higher thermal conductivity for the same average flake size owing to better flake alignment. The possibility of up to 600X enhancement of the thermal conductivity of plastic materials by coating them with the thin graphene laminate films has important practical implications.
Concentrated electric field and its energy in materials, containing nanofibers, are discussed. It is shown that the electric field in the vicinity of the end of a fiber is proportional to the external applied field and to the fiber length, whilst it
is inversely proportional to the fiber diameter. Specific electrostatic energy of a fiber in a sample under the action of external applied field is calculated. This energy appears to be negative and proportional to the ratio of the fiber length to its diameter. This means that longer fibers are more stable than the shorter ones.
We report the exfoliation of graphite in aqueous solutions under high shear rate [$sim10^8s^{-1}$] turbulent flow conditions, with a 100% exfoliation yield. The material is stabilized without centrifugation at concentrations up to 100 g/L using carbo
xymethylcellulose sodium salt to formulate conductive printable inks. The sheet resistance of blade coated films is below$sim2Omega/square$. This is a simple and scalable production route for graphene-based conductive inks for large area printing in flexible electronics.
The conductive domain wall (CDW) is extensively investigated in ferroelectrics, which can be considered as a quasi-two-dimensional reconfigurable conducting channel embedded into an insulating material. Therefore, it is highly important for the appli
cation of ferroelectric nanoelectronics. Hitherto, most CDW investigations are restricted in oxides, and limited work has been reported in non-oxides to the contrary. Here, by successfully synthesizing the non-oxide ferroelectric Sn2P2S6 single crystal, we observed and confirmed the domain wall conductivity by using different scanning probe techniques which origins from the nature of inclined domain walls. Moreover, the domains separated by CDW also exhibit distinguishable electrical conductivity due to the interfacial polarization charge with opposite signs. The result provides a novel platform for understanding electrical conductivity behavior of the domains and domain walls in non-oxide ferroelectrics.
سجل دخول لتتمكن من نشر تعليقات
التعليقات
جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
