A team at QuTech, a collaboration between TU Delft and TNO, has demonstrated the initialization, readout, and universal control of four qubits encoded in eight germanium quantum dots. Published in Nature Nanotechnology and featured on its February issue cover, this work marks a significant step toward scalable quantum computing using semiconductor qubits. The researchers created a 4×2 array of quantum dots, enabling precise control and coupling of four qubits, a critical requirement for large-scale quantum systems.
The team achieved high-fidelity quantum information transfer and entanglement swapping across qubits, with a 75% Bell state fidelity between the first and fourth qubits. This demonstrates the system’s capability to perform complex quantum operations. First author Xin Zhang noted, “Our platform allows for simulating quantum phase transitions and studying spin dynamics, paving the way for advanced quantum simulations.”
Lieven Vandersypen, who led the research, highlighted the rapid progress in quantum engineering: “What was extremely challenging a decade ago has now become achievable. This advancement underscores our commitment to making quantum computing more scalable and accessible.”
For further details, refer to the full paper here and a QuTech news article here.
February 20, 2025
