title: Nonlocal Nuclear Spin Quieting in Quantum Dot Molecules: Optically Induced Extended Two-Electron Spin Coherence Time.
abstract: We demonstrate the extension of coherence between all four two-electron spin ground states of an InAs quantum dot molecule (QDM) via nonlocal suppression of nuclear spin fluctuations in two vertically stacked quantum dots (QDs), while optically addressing only the top QD transitions. Long coherence times are revealed through dark-state spectroscopy as resulting from nuclear spin locking mediated by the exchange interaction between the QDs. Line shape analysis provides the first measurement of the quieting of the Overhauser field distribution correlating with reduced nuclear spin fluctuations.
authors: H. M. Randall Laboratory of Physics, University of Michigan, Ann Arbor, Michigan 48104, USA.|Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, Michigan 48109, USA.
authors: Colin M
authors: CM
authors: Chow
authors: H. M. Randall Laboratory of Physics, University of Michigan, Ann Arbor, Michigan 48104, USA.
authors: Aaron M
authors: AM
authors: Ross
authors: Naval Research Laboratory, Washington D.C. 20375, USA.|HRL Laboratories, LLC, 3011 Malibu Canyon Road, Malibu, California 90265, USA.
authors: Danny
authors: D
authors: Kim
authors: Naval Research Laboratory, Washington D.C. 20375, USA.
authors: Daniel
authors: D
authors: Gammon
authors: Naval Research Laboratory, Washington D.C. 20375, USA.
authors: Allan S
authors: AS
authors: Bracker
authors: Department of Physics, University of California San Diego, La Jolla, California 92093, USA.
authors: L J
authors: LJ
authors: Sham
authors: H. M. Randall Laboratory of Physics, University of Michigan, Ann Arbor, Michigan 48104, USA.|Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, Michigan 48109, USA.
authors: Duncan G
authors: DG
authors: Steel