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Many-body interferometry with semiconductor spins
D Jirovec1, S Reale1, P Cova Fariña1
1QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, Netherlands.
Science (New York, N.Y.)
|April 9, 2026
Summary
Researchers developed a new spectroscopy method for quantum simulators using germanium quantum dots. This technique allows studying up to eight interacting spins, revealing a transition toward chaotic phases in quantum systems.
Area of Science:
- Quantum Simulation
- Condensed Matter Physics
- Quantum Computing Hardware
Background:
- Classical hardware struggles with simulating complex many-body quantum phenomena.
- Semiconductor quantum dots offer electrical control and scalability for quantum simulation.
- Challenges in nanofabrication and controlling multiple interactions limit many-body studies in quantum dots.
Purpose of the Study:
- To develop a spectroscopy protocol for studying many-body phenomena in semiconductor quantum dots.
- To enable precise energy spectrum reconstruction of interacting spin systems.
- To investigate the transition from localized to chaotic phases in quantum dot systems.
Main Methods:
- Utilized a 2-×-4 array of gate-defined germanium quantum dots.
- Employed Ramsey interferometry for spin state manipulation.
- Applied adiabatic mapping of many-body eigenstates to single-spin eigenstates for spectrum reconstruction.
Main Results:
- Successfully performed spectroscopy on up to eight interacting spins.
- Observed signatures of a crossover from localization to a chaotic phase as interaction strength increased.
- Demonstrated a complete energy spectrum reconstruction protocol.
Conclusions:
- The developed spectroscopy method advances the study of many-body phenomena in quantum dot systems.
- The observed phase transition is a significant step toward exploring complex quantum behaviors.
- Germanium quantum dots show promise for scalable quantum simulation platforms.
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