Spin Rotation Studies Research Articles

Weak ferromagnetic ordering in the anomalous field-insensitive heavy-fermion state in

Abstract Zero field (ZF) and transverse field (TF) muon spin relaxation and rotation ( μ SR ) study has been carried out in filled-skutterudite SmOs 4 Sb 12 in order to investigate the magnetically robust heavy-fermion (HF) state and the weak ferromagnetic anomaly appearing below ∼ 2.5 K . A large-amplitude oscillating signal appears in the ZF- μ SR spectra at low temperatures, confirming that the weak ferromagnetic anomaly is an intrinsic bulk property. Two components with the fraction ratio of ∼ 2 : 1 exist both in the ZF- μ SR spectra of the ferromagnetically ordered state and the TF- μ SR FFT spectra in applied fields along the 〈 0 0 1 〉 direction. This observation can be explained consistently based on the most probable muon stopping site indicated from the value of the static nuclear dipolar width in Kubo–Toyabe function in the high-temperature ZF- μ SR spectra. Analysis reveals that the spontaneous magnetic moment M s lies along the 〈 0 0 1 〉 direction and the size of M s is largely suppressed, indicating that the weak ferromagnetic moment is carried by itinerant heavy quasiparticles.

Publisher's Note: Short-range magnetic ordering process for the triangular-lattice compoundNiGa2S4: A positive muon spin rotation and relaxation study [Phys. Rev. B77, 092403 (2008)

Publisher's Note: Short-range magnetic ordering process for the triangular-lattice compound<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi mathvariant="normal">Ni</mml:mi><mml:msub><mml:mi mathvariant="normal">Ga</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:msub><mml:mi mathvariant="normal">S</mml:mi><mml:mn>4</mml:mn></mml:msub></mml:mrow></mml:math>: A positive muon spin rotation and relaxation study [Phys. Rev. B<b>77</b>, 092403 (2008)

Muon spin rotation with pulsed sources: Fundamental and application-oriented aspects of synchronous pulsed magnetic fields

In a pulsed polarized source of muons, such as the ISIS Facility at the Rutherford Laboratory (UK), external fields with a duration as short as a few muon’s life-times (typically 20 μs) and synchronous to the muon pulse can be applied. Here we present a muon spin rotation (μSR) study in which an external pulsed magnetic field and/or field gradient, generated by a laminar current-loop method, are applied to investigate new properties. Field gradients are exploited for directly imaging the implantation depth distribution of positive muons in metals. Pulsed uniform magnetic fields are shown suitable for the direct measurement of the sudden-to-adiabatic crossover and, when appropriately delayed with respect to the muon pulse, are expected to be crucial for the experimental study of the delayed muonium formation.

μ- spin rotation studies on graphite and its second-stage rubidium intercalation compound. Evidence for a paramagnetic chemical shift

The precession frequencies of negative-muon spin rotation in highly oriented pyrolytic graphite and its second stage Rb compound were measured at room temperature. The results showed that a μ - C-C bond is formed from sp 2 hybrid orbitals involving the partially filled p z orbital and that intercalation influences the σ as well as the π bonds.