Southwest Quantum Information and Technology

Phase-tuned entangled state generation between distant spin qubits

Presenting Author: Clemens Matthiesen, UC Berkeley, Cambridge
Contributing Author(s): Robert Stockill, Megan Stanley, Lukas Huthmacher, Claire Le Gall, Pai Peng, Hartmut Haeffner, and Mete Atature

Entanglement is the central resource in quantum information processing, sensing and communication. Distribution of entanglement through non-local interactions, using photon interference and detection, is an attractive feature of flexible computation architectures where spatially separate nodes are locally controlled and connected via photonic channels. I will present very recent work from the Atatüre group in Cambridge on the generation of controllable entangled states between two electron spins confined in optically active indium-gallium-arsenide (InGaAs) quantum dots (QD) situated metres apart. The combination of a minimal single-photon state-projection scheme and the strong coherent light-matter interaction in these systems enables a distant entanglement rate of 7.3 kHz, the highest reported to date. With full control over the single-photon interference, we demonstrate the creation of entangled states with arbitrary phase. In the outlook I will discuss some limiting features of this semiconductor system [1], and highlight alternative venues for electron spin qubits trapped in vacuum [2]. [1] R. Stockill et al., Nature Comms 7, 12745 (2016). [2] P. Peng, C. Matthiesen, H Häffner, arXiv:1611.00130 [quant-ph] (2016).

(Session 13 : Saturday from 4:45pm - 5:15pm)