Towards a Quantum Memory in Semiconductor Quantum Dots.

The 105 nuclear spins which form the mesoscopic environment experienced by an electron in a semiconductor quantum dot (QD) are the predominant source of noise in the system. As such, they decohere the quantum state of the electron on a timescale of a few nanoseconds. The result is that, whilst QD's have excellent optical properties, their lack of a long-lived matter qubit limits their use in
applications such as quantum networks. If one could harness the nuclear spin environment for the storage of quantum information, QD's would be a promising platform for quantum communication.
Our group has already demonstrated a coherent interface between a QD electron and its nuclearspin environment. Using this interface, this work aims to experimentally realise a QD quantum memory based on storing information in magnonic modes. Moreover, with the electron providing proxy control over the nuclear-spin ensemble one can investigate the rich physics of this many-body system. For example, one could imagine generating exotic states of the spin-bath such as Schrödinger-cat states.