Controlled tunneling induced dephasing of Rabi rotations for ultra-high fidelity hole spin initialization

Abstract

We report the sub-picosecond initialization of a single heavy hole spin in a self-assembled quantum dot with >98.5 % fidelity and without external magnetic field. Using an optically adressable charge and spin storage device we tailor the relative electron and hole tunneling escape timescales from the dot and simultaneously achieve high-fidelity initialization, long hole storage times and high efficiency readout via a photocurrent signal. We measure electric field-dependent Rabi oscillations of the neutral and charged exciton transitions in the ultrafast tunneling regime and demonstrate that tunneling induced dephasing (TID) of excitonic Rabi rotations is the major source for the intensity damping of Rabi oscillations in the low Rabi frequency, low temperature regime. Our results are in very good quantitative agreement with quantum-optical simulations revealing that TID can be used to precisely measure tunneling escape times and extract changes in the Coulomb binding energies for different charge configurations of the quantum dot. Finally, we demonstrate that for sub-picosecond electron tunneling escape TID of a coherently driven exciton transition facilitates ultrafast hole spin initialization with near-unity fidelity.

References in corpus (5)

• Phonon induced Rabi frequency renormalization of optically driven single InGaAs/GaAs quantum dots
• Fast optical preparation, control and read-out of single quantum dot spin
• Recent advances in exciton based quantum information processing in quantum dot nanostructures
• High-fidelity initialization of long-lived quantum dot hole spin qubits by reduced fine-structure splitting
• Selective Optical Charge Generation, Storage and Readout in a Single Self Assembled Quantum Dot

Cited by in corpus (7)

• Reproducibility of high-performance quantum dot single-photon sources
• Quantum Fingerprints in Higher Order Correlators of a Spin Qubit
• High-fidelity initialization of long-lived quantum dot hole spin qubits by reduced fine-structure splitting
• Deterministic assembly of a charged quantum dot-micropillar cavity device
• Precise simulation for single-hole spin control in semiconductor quantum dots
• Passive stabilization of hole spin qubit using optical Stark effect
• Spin-orbit-induced hole spin relaxation in a quantum dot molecule: the effect of $s$-$p$ coupling