Rotational Doppler effect in magnetic resonance

Abstract

We compute the shift in the frequency of the spin resonance in a solid that rotates in the field of a circularly polarized electromagnetic wave. Electron-spin resonance, nuclear magnetic resonance, and ferromagnetic resonance are considered. We show that contrary to the case of the rotating LC circuit, the shift in the frequency of the spin resonance has strong dependence on the symmetry of the receiver. The shift due to rotation occurs only when rotational symmetry is broken by the anisotropy of the gyromagnetic tensor, by the shape of the body or by magnetocrystalline anisotropy. General expressions for the resonance frequency and power absorption are derived and implications for experiment are discussed.

Spin-dependent inertial force and spin current in accelerating systems

“…(14), the Pauli-Schrödinger equation for the upper component of a Dirac spinor, namely, the two-component electron wave function, is obtained in the rotating frame as 33…”

“…7 Single quantum excitations of vibration, namely, phonons, can be controlled in a piezoelectric acoustic wave resonator. 8 There has been theoretical work on effects of mechanical rotation on nanostructured magnetism, [9][10][11][12][13][14][15] the coupling of nanomechanical vibration and magnetism, [16][17][18][19] and the phonon-spin coupling related to spin relaxation. [20][21][22][23][24][25][26] However, the contribution of the spin-orbit interaction (SOI) in accelerating frames has not been thoroughly studied in previous papers.…”

Renormalization of the tunnel splitting in a rotating nanomagnet

“…In such experiments the particles retain some mechanical freedom. This inspired recent theoretical work on quantum mechanics of rotating magnets [23][24][25][26] . In this paper we study the tunnel splitting in a nanomagnet that is free to rotate about its magnetic anisotropy axis.…”

Renormalization of spin-rotation coupling

“…In Ref. 21 , the frequency shift of ESR due to rotation was pointed out as ω ′ ESR = ω ESR − Ω for an isotropic crystal. By taking account of the interband mixing, the shift reads…”

“…Einstein-de Haas effect in a NiFe film on a microcantilever 19 and mechanical torque due to spin flip on a torsion oscillator 20 were observed in experiment. Theoretically, rotational doppler shift in magnetic resonance 21 and effects of mechanical torque in nanostructure [22][23][24][25][26][27][28][29][30] are studied. These phenomena essentially rely on the spin-rotation coupling, H S .…”