A photonic link for donor spin qubits in silicon”

Wednesday, April 19, 2017 - 4:00pm
Stephanie Simmons
Speaker's Institution: 
Simon Fraser University

Atomically identical donor spin qubits in silicon offer excellent native quantum
properties, which match or outperform many qubit rivals. To scale up such systems it
would be advantageous to connect silicon donor spin qubits in a cavity-QED
architecture. Many proposals in this direction introduce strong electric dipole
interactions to the otherwise largely isolated spin qubit ground state in order to couple
to superconducting cavities. Here I present an alternative approach, which uses the
built-in strong electric dipole (optical) transitions of singly-ionized double donors in
silicon. These donors, such as chalcogen donors S^$+$, Se^$+$ and Te^$+$, have the
same ground-state spin Hamiltonians as shallow donors yet offer mid-gap binding
energies and mid-IR optical access to excited orbital states. This photonic link is
spin-selective which could be harnessed to measure and couple donor qubits using
photonic cavity-QED at 4.2K. I will present preliminary data in support of this
approach, including 4.2K optical initialization/readout in Earth's magnetic field, where
long T1 and T2 times have been measured.