Scanning SQUID susceptometry images the local magnetization and
susceptibility of a sample. By accurately modeling the SQUID signal we can
determine the physical properties such as the penetration depth and
permeability of superconducting samples. We calculate the scanning SQUID
susceptometry signal for a superconducting slab of arbitrary thickness with
isotropic London penetration depth, on a non-superconducting substrate, where
both slab and substrate can have a paramagnetic response that is linear in the
applied field. We derive analytical approximations to our general expression in
a number of limits. Using our results, we fit experimental susceptibility data
as a function of the sample-sensor spacing for three samples: 1) delta-doped
SrTiO3, which has a predominantly diamagnetic response, 2) a thin film of
LaNiO3, which has a predominantly paramagnetic response, and 3) a
two-dimensional electron layer (2-DEL) at a SrTiO3/AlAlO3 interface, which
exhibits both types of response. These formulas will allow the determination of
the concentrations of paramagnetic spins and superconducting carriers from fits
to scanning SQUID susceptibility measurements.
Description
Scanning SQUID Susceptometry of a paramagnetic superconductor
%0 Generic
%1 kirtley2012scanning
%A Kirtley, J. R.
%A Kalisky, B.
%A Bert, J. A.
%A Bell, C.
%A Hikita, Y.
%A Hwang, H. Y.
%A Ngai, J. H.
%A Segal, Y.
%A Walker, F. J.
%A Ahn, C. H.
%A Moler, K. A.
%D 2012
%K chiral
%T Scanning SQUID Susceptometry of a paramagnetic superconductor
%U http://arxiv.org/abs/1204.3355
%X Scanning SQUID susceptometry images the local magnetization and
susceptibility of a sample. By accurately modeling the SQUID signal we can
determine the physical properties such as the penetration depth and
permeability of superconducting samples. We calculate the scanning SQUID
susceptometry signal for a superconducting slab of arbitrary thickness with
isotropic London penetration depth, on a non-superconducting substrate, where
both slab and substrate can have a paramagnetic response that is linear in the
applied field. We derive analytical approximations to our general expression in
a number of limits. Using our results, we fit experimental susceptibility data
as a function of the sample-sensor spacing for three samples: 1) delta-doped
SrTiO3, which has a predominantly diamagnetic response, 2) a thin film of
LaNiO3, which has a predominantly paramagnetic response, and 3) a
two-dimensional electron layer (2-DEL) at a SrTiO3/AlAlO3 interface, which
exhibits both types of response. These formulas will allow the determination of
the concentrations of paramagnetic spins and superconducting carriers from fits
to scanning SQUID susceptibility measurements.
@misc{kirtley2012scanning,
abstract = {Scanning SQUID susceptometry images the local magnetization and
susceptibility of a sample. By accurately modeling the SQUID signal we can
determine the physical properties such as the penetration depth and
permeability of superconducting samples. We calculate the scanning SQUID
susceptometry signal for a superconducting slab of arbitrary thickness with
isotropic London penetration depth, on a non-superconducting substrate, where
both slab and substrate can have a paramagnetic response that is linear in the
applied field. We derive analytical approximations to our general expression in
a number of limits. Using our results, we fit experimental susceptibility data
as a function of the sample-sensor spacing for three samples: 1) delta-doped
SrTiO3, which has a predominantly diamagnetic response, 2) a thin film of
LaNiO3, which has a predominantly paramagnetic response, and 3) a
two-dimensional electron layer (2-DEL) at a SrTiO3/AlAlO3 interface, which
exhibits both types of response. These formulas will allow the determination of
the concentrations of paramagnetic spins and superconducting carriers from fits
to scanning SQUID susceptibility measurements.},
added-at = {2012-04-18T19:19:27.000+0200},
author = {Kirtley, J. R. and Kalisky, B. and Bert, J. A. and Bell, C. and Hikita, Y. and Hwang, H. Y. and Ngai, J. H. and Segal, Y. and Walker, F. J. and Ahn, C. H. and Moler, K. A.},
biburl = {https://www.bibsonomy.org/bibtex/2af0d3a16c708148c11a99725eacef243/vakaryuk},
description = {Scanning SQUID Susceptometry of a paramagnetic superconductor},
interhash = {c9eecc4f754fcad69868bc54e09d969d},
intrahash = {af0d3a16c708148c11a99725eacef243},
keywords = {chiral},
note = {cite arxiv:1204.3355 Comment: 11 pages, 13 figures},
timestamp = {2012-04-18T19:19:27.000+0200},
title = {Scanning SQUID Susceptometry of a paramagnetic superconductor},
url = {http://arxiv.org/abs/1204.3355},
year = 2012
}