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\@writefile{toc}{\contentsline {subsection}{\numberline {2.1}The 4-Wire Technique and Alternation}{2}}
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\@writefile{lof}{\contentsline {figure}{\numberline {3}{\ignorespaces The control boxes for the 4-wire measurement: Top: Keithley 6220 precision current source; Bottom: Keithley 2812A nanovoltmeter; Left: Lakeshore temperature controller. \relax }}{4}}
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\@writefile{lof}{\contentsline {figure}{\numberline {4}{\ignorespaces The rear of the 6220/2812 pair, set up for Delta measurements. For diode measurements, the two serial connections between them are replaced by a GPIB cable.\relax }}{4}}
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\@writefile{lof}{\contentsline {figure}{\numberline {5}{\ignorespaces The cold head. The sample mounts to the copper backing at the top, and the leads are soldered to the pins.\relax }}{6}}
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\@writefile{toc}{\contentsline {subsection}{\numberline {3.1}Calibrating Thermometers}{6}}
\@writefile{toc}{\contentsline {subsection}{\numberline {3.2}Sample Mounting}{7}}
\@writefile{toc}{\contentsline {subsection}{\numberline {3.3}Sample and Thermometer Wiring}{7}}
\@writefile{lof}{\contentsline {figure}{\numberline {6}{\ignorespaces How the samples are mounted on the copper sample holder. The two thermometers bracket the sample temperature. The sapphire layers provide good thermal contact and electrical insulation.\relax }}{8}}
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\@writefile{toc}{\contentsline {subsection}{\numberline {3.6}Getting Ready to Take Data}{10}}
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\@writefile{toc}{\contentsline {section}{\numberline {4}Some Notes on the Elective Measurements}{12}}
\@writefile{toc}{\contentsline {subsection}{\numberline {4.1}Non-Alternating Measurements (for Diodes)}{12}}
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\@writefile{toc}{\contentsline {subsection}{\numberline {4.2}High Temperature Measurements and Furnace Use (for the $T_C$ of Ni)}{14}}
\@writefile{toc}{\contentsline {section}{\numberline {5}Making BSCCO}{15}}
\@writefile{toc}{\contentsline {subsection}{\numberline {5.1}The Process}{15}}
\@writefile{toc}{\contentsline {section}{\numberline {6}References}{16}}
\@writefile{toc}{\contentsline {subsection}{\numberline {6.1}File and Manual Locations}{16}}
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\@writefile{toc}{\contentsline {section}{\numberline {7}Theoretical Background}{18}}
\@writefile{toc}{\contentsline {subsection}{\numberline {7.1}The Drude Model}{18}}
\@writefile{lof}{\contentsline {figure}{\numberline {9}{\ignorespaces The Drude picture of a metal. Electrons are tiny, charged pinballs rattling past obstacles in the general direction of the applied field.\relax }}{18}}
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\@writefile{lof}{\contentsline {figure}{\numberline {10}{\ignorespaces The in-phase part of $\sigma (\omega )$ for a metal ($k=0$). As $f\rightarrow 0$ ($\tau \rightarrow \infty $), the energy absorption per cycle peaks more and more strongly about $\omega =0$.\relax }}{20}}
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\@writefile{toc}{\contentsline {section}{\numberline {8}What affects the Resistivity}{21}}
\@writefile{toc}{\contentsline {subsection}{\numberline {8.1}Impurity Scattering in Metals--a Surprising Temperature-Independence}{21}}
\@writefile{lof}{\contentsline {figure}{\numberline {11}{\ignorespaces Fermi Ball. The idea is that each momentum owns a particular volume of momentum space (specifically $h^3/V$, where $V$ is the volume of the sample). So the electrons, of which only two can ever have the same momentum, must stack up.\relax }}{22}}
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\@writefile{lof}{\contentsline {figure}{\numberline {12}{\ignorespaces Current-carrying state of the Fermi ball. The Fermi ball is displaced by the average momentum shift $e\mathaccent "017E\relax {E}\tau $. One electron has been scattered backwards, and another is going to hop into its place. The net current is density comes from the momentum states in the crescent on the right. \relax }}{23}}
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\@writefile{lof}{\contentsline {figure}{\numberline {13}{\ignorespaces Cartoon of a particular phonon on a centered square lattice. The blue atoms are displaced from their equilibrium lattice positions.\relax }}{26}}
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\@writefile{lof}{\contentsline {figure}{\numberline {14}{\ignorespaces Electrons scattering from phonons (point particle picture). The lattice ions in blue are displaced from their equilibrium positions. Electrons (tiny green dots) are drawn to regions of temporarily higher positive charge density.\relax }}{26}}
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\@writefile{lof}{\contentsline {figure}{\numberline {15}{\ignorespaces Phonon scattering cartoon (momentum space version). Here $q$ is the phonon momentum and the initial and final electron states are taken to be on the Fermi surface.\relax }}{27}}
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\@writefile{lof}{\contentsline {figure}{\numberline {16}{\ignorespaces A schematic of the energy bands in a crystalline solid.\relax }}{30}}
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\@writefile{toc}{\contentsline {subsection}{\numberline {8.4}Conduction Electrons, Valence Holes, $\Delta $, and Doping}{30}}
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\@writefile{lof}{\contentsline {figure}{\numberline {18}{\ignorespaces Band bending across an np junction.\relax }}{33}}
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\@writefile{toc}{\contentsline {subsection}{\numberline {9.1}Itenerant Ferromagnetism in Nickel: Changing $\sigma _a$}{37}}
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\@writefile{lof}{\contentsline {figure}{\numberline {19}{\ignorespaces This ledge in the resistance indicates the onset of the SC transition to zero resistance. The sample was cut from Nb wire purchased from a jewelry supplier on an online auction site. The low temperature limit of the apparatus prevents you from seeing the full transition.\relax }}{39}}
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