Theory of phonon-modulated electron spin relaxation time based on the projection-reduction method

• Published in: Chinese physics B Vol. 23; no. 8; pp. 436 - 443
• Main Authors: Kang, Nam Lyong, Choi, Sang Don
• Format: Journal Article
• Language: English
• Published: 01.08.2014
• Subjects: Acoustics; Constants; Deformation; Electron spin; Emission; Magnetic fields; Phonons; Relaxation time; 声学声子; 弛豫时间; 投影; 电子自旋; 相互作用系统; 自旋轨道耦合; 调制; 还原法
• ISSN: 1674-1056; 2058-3834; 1741-4199
• DOI: 10.1088/1674-1056/23/8/087102

This paper introduces a new method for a formula for electron spin relaxation time of a system of electrons interacting with phonons through phonon-modulated spin-orbit coupling using the projection-reduction method. The phonon absorption and emission processes as well as the photon absorption and emission processes in all electron transition processes can be explained in an organized manner, and the result can be represented in a diagram that can provide intuition for the quantum dynamics of electrons in a solid. The temperature （T） dependence of electron spin relaxation times （T1） in silicon is T1 ∝ T-1.07 at low temperatures and T1 ∝ T-3.3 at high temperatures for acoustic deformation constant Pad = 1.4 × 10^7 eV and optical deformation constant Pod = 4.0 × 10^17 eV/m. This means that electrons are scattered by the acoustic deformation phonons at low temperatures and optical deformation phonons at high temperatures, respectively. The magnetic field （B） dependence of the relaxation times is T1 ∝ B-2.7 at 100 K and T1 ∝ B-2.3 at 150 K, which nearly agree with the result of Yafet, T1 ∝ B-3.0- B -2.5.