Optically Pumped NMR Measurements of the Electron Spin Polarization in GaAs Quantum Wells near Landau Level Filling Factor nu=1/3

(2) Bell Laboratories; K. W. West (2) ((1) Dept. of Physics; L. N. Pfeiffer (2); Lucent Technologies); N. N. Kuzma (1); P. Khandelwal (1); S. E. Barrett (1); Yale University

arxiv: cond-mat/9801199 · v2 · submitted 1998-01-20 · ❄️ cond-mat.mes-hall · cond-mat.str-el

Optically Pumped NMR Measurements of the Electron Spin Polarization in GaAs Quantum Wells near Landau Level Filling Factor nu=1/3

P. Khandelwal (1) , N. N. Kuzma (1) , S. E. Barrett (1) , L. N. Pfeiffer (2) , K. W. West (2) ((1) Dept. of Physics , Yale University , (2) Bell Laboratories , Lucent Technologies) This is my paper

classification ❄️ cond-mat.mes-hall cond-mat.str-el

keywords nearquantumdataelectronmeasurementsopticallypolarizationpumped

0 comments

read the original abstract

The Knight shift of Ga-71 nuclei is measured in two different electron-doped multiple quantum well samples using optically pumped NMR. These data are the first direct measurements of the electron spin polarization, P(nu,T)=<Sz(nu,T)>/max<Sz>, near nu=1/3. The P(T) data at nu=1/3 probe the neutral spin-flip excitations of a fractional quantum Hall ferromagnet. In addition, the saturated P(nu) drops on either side of nu=1/3, even in a Btot=12 Tesla field. The observed depolarization is quite small, consistent with an average of about 0.1 spin-flips per quasihole (or quasiparticle), a value which does not appear to be explicable by the current theoretical understanding of the FQHE near nu=1/3.

This paper has not been read by Pith yet.

Optically Pumped NMR Measurements of the Electron Spin Polarization in GaAs Quantum Wells near Landau Level Filling Factor nu=1/3

discussion (0)