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arXiv · 0710.3847

Coherent transfer of light polarization to electron spins in a semiconductor

Hideo Kosaka·Hideki Shigyou·Yasuyoshi Mitsumori·Yoshiaki Rikitake·Hiroshi Imamura·Takeshi Kutsuwa·Koichiro Arai·Keiichi Edamatsu
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Abstract

We demonstrate that the superposition of light polarization states is coherently transferred to electron spins in a semiconductor quantum well. By using time-resolved Kerr rotation we observe the initial phase of Larmor precession of electron spins whose coherence is transferred from light. To break the electron-hole spin entanglement, we utilized the big discrepancy between the transverse g-factors of electrons and light holes. The result encourages us to make a quantum media converter between flying photon qubits and stationary electron spin qubits in semiconductors.

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Hideo Kosaka, Hideki Shigyou, Yasuyoshi Mitsumori, Yoshiaki Rikitake, Hiroshi Imamura, Takeshi Kutsuwa, Koichiro Arai, Keiichi Edamatsu. 2007-10-20. Coherent transfer of light polarization to electron spins in a semiconductor. https://doi.org/10.1103/physrevlett.100.096602

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