Control of hole g-factors and spin initialization technique in single quantum dots

2015 Fiscal Year Final Research Report

• Project/Area Number: 26800162
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Condensed matter physics I
• Research Institution: Hokkaido University
• Principal Investigator: Kaji Reina 北海道大学, 工学(系)研究科(研究院), 助教 (40640751)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: 量子ナノ構造 / 正孔スピン / g因子 / スピン初期化技術 / 価電子帯混合

Outline of Final Research Achievements

Today, the spin control in the semiconductor quantum dots (QDs) has gained considerable attention. Since the hole spin coherence is expected to be longer than that of the electron due to weak hyperfine interaction, the usage of hole spin is especially favored.
First, we studied the correlations between the g-factors and the degree of valence band mixing (VBM) in quantum rings, and found that the hole g-factor shows the anisotropic feature and its magnitude depends on the degree of VBM. Moreover, the effects of the shape and strain anisotropy were discussed theoretically. Next, we tried to improve the S/N ratio of Kerr rotation spectroscopy, and verified the negative trion dynamics in CdTe quantum well. Further, we performed the Hanle measurement in a single QD and observed the anomalous curve implying the formation of in-plane nuclear field.
All results in this work are quite important for the demonstration of the hole spin manipulation.

Free Research Field

半導体光物性