Readout and control of the spin-orbit states of two coupled acceptor atoms in a silicon transistor.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 30539142.
- Also identified by DOI 10.1126/sciadv.aat9199 and PMC identifier 6286166.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Coupling spin qubits to electric fields is attractive to simplify qubit manipulation and couple qubits over long distances. Electron spins in silicon offer long lifetimes, but their weak spin-orbit interaction makes electrical coupling challenging. Hole spins bound to acceptor dopants, spin-orbit-coupled <i>J</i> = 3/2 systems similar to Si vacancies in SiC and single Co dopants, are an electrically active spin system in silicon. However, <i>J</i> = 3/2 systems are much less studied than <i>S</i> = 1/2 electrons, and spin readout has not yet been demonstrated for acceptors in silicon. Here, we study acceptor hole spin dynamics by dispersive readout of single-hole tunneling between two coupled acceptors in a nanowire transistor. We identify <i>m</i> <sub><i>J</i></sub> = ±1/2 and <i>m</i> <sub><i>J</i></sub> = ±3/2 levels, and we use a magnetic field to overcome the initial heavy-light hole splitting and to tune the <i>J</i> = 3/2 energy spectrum. We find regimes of spin-like (+3/2 to -3/2) and charge-like (±1/2 to ±3/2) relaxations, separated by a regime of enhanced relaxation induced by mixing of light and heavy holes. The demonstrated control over the energy level ordering and hybridization are new tools in the <i>J</i> = 3/2 system that are crucial to optimize single-atom spin lifetime and electrical coupling.