Optical Spin Initialization and Non-Destructive Measurement in a Quantum Dot Molecule

Abstract

The spin of an electron in a self-assembled InAs/GaAs quantum dot molecule is optically prepared and measured through the trion triplet states. A longitudinal magnetic field is used to tune two of the trion states into resonance, forming a superposition state through asymmetric spin exchange. As a result, spin-flip Raman transitions can be used for optical spin initialization, while separate trion states enable cycling transitions for non-destructive measurement. With two-laser transmission spectroscopy we demonstrate both operations simultaneously, something not previously accomplished in a single quantum dot.

Accepted for publication in Phys. Rev. Lett

References in corpus (10)

• Direct Observation of Controlled Coupling in an Individual Quantum Dot Molecule
• Resonance fluorescence from a coherently driven semiconductor quantum dot in a cavity
• Coherent Population Trapping of an Electron Spin in a Single Negatively Charged Quantum Dot
• Fast optical preparation, control and read-out of single quantum dot spin
• Electrically tunable g-factors in quantum dot molecular spin states
• Bistability of the Nuclear Polarisation created through optical pumping in InGaAs Quantum Dots
• Optically Probing Spin and Charge Interactions in an Tunable Artificial Molecule
• Nonlinear dynamics of quantum dot nuclear spins
• Fine structure and optical pumping of spins in individual semiconductor quantum dots
• The Nuclear Spin Nanomagnet