title: Analyzing Longitudinal Magnetoresistance Asymmetry to Quantify Doping Gradients: Generalization of the van der Pauw Method.
abstract: A longitudinal magnetoresistance asymmetry (LMA) between a positive and negative magnetic field is known to occur in both the extreme quantum limit and the classical Drude limit in samples with a nonuniform doping density. By analyzing the current stream function in van der Pauw measurement geometry, it is shown that the electron density gradient can be quantitatively deduced from this LMA in the Drude regime. Results agree with gradients interpolated from local densities calibrated across an entire wafer, establishing a generalization of the van der Pauw method to quantify density gradients.
authors.affiliation: Electrical Engineering and Computer Science, Northwestern University, Evanston, Illinois 60208, USA.
authors.forename: Wang
authors.initials: W
authors.lastname: Zhou
authors.affiliation: Electrical Engineering and Computer Science, Northwestern University, Evanston, Illinois 60208, USA.
authors.forename: H M
authors.initials: HM
authors.lastname: Yoo
authors.affiliation: Electrical Engineering and Computer Science, Northwestern University, Evanston, Illinois 60208, USA.
authors.forename: S
authors.initials: S
authors.lastname: Prabhu-Gaunkar
authors.affiliation: Laboratory for Solid State Physics, ETH Zürich, 8093 Zürich, Switzerland.
authors.forename: L
authors.initials: L
authors.lastname: Tiemann
authors.affiliation: Laboratory for Solid State Physics, ETH Zürich, 8093 Zürich, Switzerland.
authors.forename: C
authors.initials: C
authors.lastname: Reichl
authors.affiliation: Laboratory for Solid State Physics, ETH Zürich, 8093 Zürich, Switzerland.
authors.forename: W
authors.initials: W
authors.lastname: Wegscheider
authors.affiliation: Electrical Engineering and Computer Science, Northwestern University, Evanston, Illinois 60208, USA.
authors.forename: M
authors.initials: M
authors.lastname: Grayson