Leakage-protected idle operation of a triangular exchange-only spin qubit

Demonstrates a leakage-protected idle point created by equal, simultaneous three-way exchange in a triangular exchange-only qubit.

Key Results

Equal couplings create a gap (E_g=3J/2) between the (S=1/2) logical and (S=3/2) leakage manifolds.
The exchange operation is an identity on the logical qubit up to phase.
Measured dephasing outperforms conventional exchange-off idling for (E_g/h<60) MHz.