Theoretical Modeling of the Nuclear‐Field Induced Tuning of the Electron Spin Precession for Localized Spins

Abstract

This work is devoted to a theoretical analysis of the effect of nuclear-induced field (Overhauser field) on the Larmor frequencies of electron spins under the periodic pulsed excitation. To describe the dynamical nuclear spin polarization, we use the model where the optically induced Stark field determines the magnitude and direction of the Overhauser field. The Stark field strongly depends on the detuning between the photon energy of excitation and the optical transition energy in the quantum system. Detailed calculations which show that the precession frequencies of fluorine donorbound electron spins in ZnSe deviate from the linear dependence of the Larmor frequencies on the external magnetic field have been performed. A similar effect is observed for the (In,Ga)As/GaAs quantum dots, where it has been shown that the Overhauser field strongly changes the spectrum of the electron spin precession frequencies.

Interplay of spin mode locking and nuclei-induced frequency focusing in quantum dots

“…Detuned pulses can lead to the emergence of different resonances as demonstrated in Refs. [11,69]. There, the influence of a positive and negative detuning on NIFF is discussed, but a different model is used for the spin dynamics.…”

Dynamic Nuclear Polarization by optical Stark effect in periodically-pumped gallium arsenide

“…Analysis of the feedback between the nuclear spin system and electrons rotated into the magnetic field axis by the optical Stark effect has been recently performed in Ref. [13]. This analysis also provides a formulation of S x (B tot ) which is equivalent to the derived alternative formulation presented by Eqn (5).…”

“…However, the analysis performed in Ref. [13] is limited to the steady-state stable solutions of the coupled electron-nuclear system. We use our model to explore the hysteretic transient solutions which describe and qualitatively replicate the previously unexplained nonlinear magnetic field sweep dependent behavior in Ref.…”

“…Measurements in fluorine-doped ZnSe [11] and GaAs [12] have both revealed a DNP that is periodic in magnetic field. The former was attributed to electron spins optically rotated onto the magnetic field axis via the optical Stark effect (OSE) [13], while the cause of the latter was not conclusively identified.…”

Shielding of external magnetic field by dynamic nuclear polarization in (In,Ga)As quantum dots

“…2(c) [21,26]. It can be explained by a semi-classical description using the average spin concept and taking into account the variation of the electron-nuclear feedback strength, see below [26,28]. The feedback is maximal at the plateau centers (B x = KB 0 ), leading to a reduction of the nuclear spin fluctuations [21], while the feedback is reduced between the plateaus.…”