Latched readout for the quantum dot hybrid qubit

Abstract

A primary method of reading out a quantum dot hybrid qubit involves projection of the logical basis onto distinct charge states that are readily detected by an integrated charge sensing dot. However, in the simplest configuration, the excited charge state decays rapidly, making single-shot readout challenging. Here, we demonstrate a readout procedure where the qubit excited state is latched to a metastable charge configuration whose lifetime is tunnel rate limited, persisting here as long as 2.5 ms. Additionally, we show that working in the (4,1)-(3,2) charge configuration enables a latched readout window that is larger and more tunable than typical charge configurations, because the size of the readout window is determined by an orbital splitting rather than a valley splitting.

References in corpus (8)

• Single-shot read-out of an individual electron spin in a quantum dot
• Driven coherent oscillations of a single electron spin in a quantum dot
• Demonstration of Entanglement of Electrostatically Coupled Singlet-Triplet Qubits
• Microwave-driven coherent operations of a semiconductor quantum dot charge qubit
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Cited by in corpus (2)

• Single-shot latched readout of a quantum dot qubit using barrier gate pulsing
• Fast high-fidelity baseband reset of a latched state for quantum dot qubit readout