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15:47
Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots
Published on: November 1, 2013
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Angular momentum transfer from photon polarization to an electron spin in a gate-defined quantum dot
Takafumi Fujita1,2, Kazuhiro Morimoto3, Haruki Kiyama3,4
1Department of Applied Physics, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan. fujita@sanken.oaska-u.ac.jp.
Nature Communications
|July 18, 2019
Summary
Single photons can now control electron spins in quantum dots. This research demonstrates angular momentum transfer from photons to spins, enabling spin detection and potential quantum communication applications.
Area of Science:
- Quantum Information Science
- Solid-State Physics
- Optoelectronics
Background:
- Gate-defined quantum dots (QDs) offer tunable quantum systems for spin manipulation.
- A key challenge is interfacing these spins with photons for quantum applications.
Purpose of the Study:
- To demonstrate the excitation of single electron spins in QDs using circularly-polarized photons.
- To establish a method for detecting single photo-electrons via spin blockade.
- To confirm the transfer of angular momentum from photons to electron spins.
Main Methods:
- Utilized a double quantum dot (QD) system defined by gates.
- Employed Pauli spin blockade (PSB) to monitor inter-dot charge tunneling.
- Investigated the spin-dependent excitation of electrons by single photons.
Main Results:
- Verified that circularly-polarized photons can excite single electron spins through angular momentum transfer.
- Demonstrated the detection of single photo-electrons in a spin-up/down basis using PSB.
- Confirmed photon polarization dependence for heavy-hole exciton excitation.
Conclusions:
- Angular momentum transfer from photons to spins in QDs is experimentally verified.
- This provides a pathway for efficient spin injection and distribution of quantum information.
- Opens possibilities for advancing quantum communication technologies.
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