Theoretical study of electronic states and spin operation in coupled quantum dots

D. Goto, M. Eto

研究成果: Conference contribution

抄録

We theoretically study the electronic states and spin operation in coupled quantum dots, based on the calculations of many-body wavefunctions. We adopt a tight-binding model on a square lattice with a smooth tunnel barrier around its center. Taking into account the electron-electron interaction by the exact diagonalization method, we evaluate the spin coupling J between two electron spins, as a function of magnetic field perpendicular to the quantum dots, and show a transition from antiferromagnetic coupling (J > 0) to ferromagnetic coupling (J < 0). The coupling J is not seriously influenced by the size difference between the dots if the energy levels are tuned to match each other using the gate voltage. Next, we simulate SWAP gate operation by calculating the time development of two electron spins. A nonadiabatic change of the tunnel barrier between the quantum dots may cause operation errors, due to the contribution from high energy states. The complete exchange of the spin states could be also blocked by the spin-orbit interaction.

本文言語English
ホスト出版物のタイトルMS+S 2006 - Controllable Quantum States
ホスト出版物のサブタイトルMesoscopic Superconductivity and Spintronics, Proceedings of the International Symposium
出版社World Scientific Publishing Co. Pte Ltd
ページ239-244
ページ数6
ISBN(印刷版)9812814612, 9789812814616
出版ステータスPublished - 2008 1月 1
イベント4th International Symposium on Mesoscopic Superconductivity and Spintronics, MS+S 2006 - Atsugi, Japan
継続期間: 2006 2月 272006 3月 2

出版物シリーズ

名前MS+S 2006 - Controllable Quantum States: Mesoscopic Superconductivity and Spintronics, Proceedings of the International Symposium

Other

Other4th International Symposium on Mesoscopic Superconductivity and Spintronics, MS+S 2006
国/地域Japan
CityAtsugi
Period06/2/2706/3/2

ASJC Scopus subject areas

  • 電子工学および電気工学

フィンガープリント

「Theoretical study of electronic states and spin operation in coupled quantum dots」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル