Thermal Conductivity in Nickel at High Electron Temperatures
Investigating thermal conductivity in nickel at high electron temperatures by studying electron interactions. Detailed analysis on electron scattering processes at extreme states of matter.
Thermal Conductivity in Nickel at High Electron Temperatures
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Thermal conductivity due to s-s and s-d electron interaction in nickel at high electron temperatures Yu.V. Petrov, N.A. Inogamov L.D. Landau Institute for Theoretical Physics XXVII International Conference onEquations of State for MatterMarch 1-6, 2012, Elbrus, Kabardino-Balkaria, Russia
Scatterng of electrons with momentum and transferred momentum Electrons interact through the screened Coulomb interaction with a screening length
Frequency of collisions of s-electron with momentum with other electrons is a statistical factor
In the case of ss->ss scattering the statistical factor has a form This case was presented in Elbrus-2010 Physics of Extreme States of Matter – 2010, Chernogolovka, 2010, pp. 129-132. Н.А. Иногамов, Ю.В. Петров, Теплопроводность металлов с горячими электронами. ЖЭТФ, 2010, т. 137, вып. 3, 505-529.
When considering sd->sd scattering At electron temperature Fermi functions are is a bottom of s-band are the bottom and top of d-band is a chemical potentiall
Within the effective mass approximation Energy conservation In terms of variables and
and In terms of variables the collision frequency of s-electrons having the momentum with d-electrons takes a form
Frequency of sd-sd collisions as a two-dimensional integral in plane At given introduce polar and azimuthal angles of vector and Is the angle between and ) ( and the variable introduce polar and azimuthal angles of vector At given and and the variable Then , ,
-function After integration over because of the presence of
introduce function When integrating over
Because of dependence and we obtain For given p the frequency of collisionsis a two-dimensional integral in plane Because of after scattering d-electron remains in d-band with respect to the interval In dependence on position of point two cases arise
Case I. . It leads to In this case and At the same time and Because of the presence of integration over depends on the relative positions of segments and . It defines the boundary , of integration in plane and arguments in a function It gives 3 variants of this relative positions. Variant 1. or , Here ,
In this variant For example, for : limits of integration over
Analogously Variant 2 and , Variant 3 , are considered. Case II. , , In this case
integration over Because of the presence of gives a result which differs from zero in 4 variants Variant 1 , Variant 2 , Variant 3 , Variant 4 ,
Average s-d electron collision frequency When having the frequency of collisions of the s-electron with given momentum p we can obtain the thermal conductivity coefficient due to s-d electron scattering: Then we define the average s-d collision frequency by using its Drude relation with thermal conductivity coefficient , mean squared velocity of s-electrons and their heat capacity per unit volume
Thermal conductivity coefficient of Ni and Al due to electron-electron scattering
Average frequency of electron-electron collisions in Ni and Al as a function of electron temperature