Giant electron-spin g factors in a ferromagnetic nanoparticle

Article

关键词: ARTIFICIAL ATOMS;    METAL NANOPARTICLES;    COULOMB-BLOCKADE;    QUANTUM DOTS;    SPECTROSCOPY;    STATES;    PARTICLES;   

DOI  :  10.1103/PhysRevB.88.075303

来源: SCIE

【 摘 要 】

We utilize single-electron tunneling spectroscopy to measure the discrete energy levels in a nanometer-scale cobalt particle at T = 60 mK, and find effective single-electron spin g factors approximate to 7.3. These large g factors do not result from the typical orbital contribution to g factors, since the orbital angular momentum is quenched. Instead, they are due to nontrivial many-body excitations. A kink in the plot of conductance vs voltage and magnetic field is a signature of degenerate total spin on the particle. Spin-orbit interactions cause the new particle eigenstates to have spin that is an admixture of pure spin states. Fluctuations in the discrete energy level spacing allow for the total change in spin on the particle during a single-electron tunneling event to be Delta S' = 3/2, leading to a g factor of around 6.

【 授权许可】

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