Lecture Adel Nader
|09 februari 2012||FWN-Building 5114.0004, Nijenborgh 4, 9747 AG, Groningen|
|Speaker:||Dr. Adel Nader|
|Affiliation:||Atomic Energy Commission of Syria|
|Title:||Simple resistivity measurement|
|Date:||Thu Feb 9, 2012|
|Telephone:||+31 50 363 4419|
1) Resistivity measurement of low resistance samples consists on injecting the current between two contacts and measuring the voltage drop between two others. Though, a good resistivity determination necessitates that the potential distribution is determined into the sample in function of different parameters such as contacts configuration, sample geometry, anisotropy resistivity variation in space and ohmicity. On the other hand the resistance final expression must be easy to calculate with an acceptable numerical error.
I will present some cases where compact expressions of the resistance are given: Thin disk, anisotropic cylinder (the case of single domain superconducting disk), anisotropic paralleliped (the case of layered compounds) and the multi-layer systems. This problem can be regarded as an independent mathematical problem.
2) As an application the resistivity anisotropy of some Dichalcogenides and misfit layer compound is determined. In some cases, the resistivity anisotropy seems to be related with some charge density wave transitions. On other cases it shows an unusual behavior.
|Laatst gewijzigd:||22 oktober 2012 14:30|