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Updated: Feb 4, 2026
08:15
Synthesis of Nine-atom Deltahedral Zintl Ions of Germanium and their Functionalization with Organic Groups
Published on: February 11, 2012
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A germanium hole spin qubit.
Hannes Watzinger1, Josip Kukučka2, Lada Vukušić3
1Institute of Science and Technology Austria, Am Campus 1, 3400, Klosterneuburg, Austria. hannes.watzinger@ist.ac.at.
Nature Communications
|September 27, 2018
Summary
Researchers demonstrate two-axis control of a spin 3/2 qubit in germanium (Ge) quantum dots. This breakthrough shows Ge
Area of Science:
- Quantum Computing
- Solid-State Physics
- Materials Science
Background:
- Holes confined in quantum dots are promising candidates for spin qubits.
- Germanium (Ge) offers potential for advanced semiconductor devices.
Purpose of the Study:
- To demonstrate two-axis control of a spin 3/2 qubit in a natural Ge hut wire double quantum dot.
- To investigate the potential of Ge as a platform for fast and electrically tunable hole spin qubits.
Main Methods:
- Fabrication of a hut wire double quantum dot device in natural Ge.
- Utilizing Pauli spin blockade to enable electric dipole spin resonance (EDSR).
- Applying radio frequency electric fields for qubit manipulation.
Main Results:
- Demonstrated two-axis control of a spin 3/2 hole qubit.
- Achieved coherent hole spin oscillations with Rabi frequencies up to 140 MHz.
- Measured dephasing times of 130 ns.
Conclusions:
- Germanium is a viable platform for developing fast and electrically tunable hole spin qubits.
- The demonstrated control and coherence properties highlight Ge's potential in quantum information processing.
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