Fast Hybrid Silicon Double-Quantum-Dot Qubit

Proposes and demonstrates the hybrid qubit: a three-electron qubit in a double quantum dot that combines the speed of charge qubits with the coherence of spin qubits. Uses a (2,1)→(1,2) charge transition where spin-orbit-like mixing creates a sweet spot.

Key Results

• Gate times ~100 ps (charge-like speed)
• T₂* ~ 10 ns at sweet spot
• Three electrons in double quantum dot (not triple dot)
• Combines fast manipulation with improved dephasing protection

Links

• Journal: Physical Review Letters
• arXiv: 1201.2388

Zoo Links

• hybrid-qubit
• spin-qubit
• semiconductor-charge-qubit