Probing the Nuclear Spin-Lattice Relaxation Time at the Nanoscale

J J T Wagenaar,J M De Voogd,D J Thoen,T M Klapwijk,K M Bastiaans,T H Oosterkamp,A Endo,J Zaanen,T A De Jong,A M J Den Haan,L Bossoni,M De Wit

doi:10.1103/physrevapplied.6.014007

Abstract

Nuclear spin-lattice relaxation times are measured on copper using magnetic resonance force microscopy performed at temperatures down to 42 mK. The low temperature is verified by comparison with the Korringa relation. Measuring spin-lattice relaxation times locally at very low temperatures opens up the possibility to measure the magnetic properties of inhomogeneous electron systems realized in oxide interfaces, topological insulators and other strongly correlated electron systems such as high-Tc superconductors.

Highlights

Among the most informative probes of electron systems in solids is the nuclear spin-lattice relaxation rate 1=T1
Measuring spin-lattice relaxation times locally at very low temperatures opens up the possibility to measure the magnetic properties of inhomogeneous electron systems realized in oxide interfaces, topological insulators, and other strongly correlated electron systems such as high-Tc superconductors
In Fermi liquids like copper, the Korringa relation [1] 1=ðT1TÞ 1⁄4 const universally holds, while non-Korringa behaviors play a pivotal role in establishing the unconventional nature of various strongly interacting electron systems [2]

Summary

Introduction

Among the most informative probes of electron systems in solids is the nuclear spin-lattice relaxation rate 1=T1. This value quantifies the damping of the nuclear spin precession due to the coupling to the electron spins This in turn can be related to the momentum-averaged imaginary part of the dynamical spin susceptibility of the electron system, measured at the very low Larmor frequency of the nuclear spins. In Fermi liquids like copper, the Korringa relation [1] 1=ðT1TÞ 1⁄4 const universally holds, while non-Korringa behaviors play a pivotal role in establishing the unconventional nature of various strongly interacting electron systems [2] This mainstay of traditional NMR methods is hampered by the fact that it is a very weak signal that usually can be detected only in bulk samples [3]. The statistical polarization of the protons is measured, since the Boltzmann polarization is too small to detect

Methods

Results

Conclusion