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Updated: Jun 21, 2026
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Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
Emulation of a quantum spin with a superconducting phase qudit
Matthew Neeley1, Markus Ansmann, Radoslaw C Bialczak
1Department of Physics, University of California at Santa Barbara (UCSB), Santa Barbara, CA 93106, USA.
Science (New York, N.Y.)
|August 8, 2009
Summary
Superconducting phase qudits (d-level systems) up to d=5 were operated and controlled. These multilevel qudits enabled emulation of spin dynamics and measurement of quantum properties like Berry
Area of Science:
- Quantum Information Processing
- Superconducting Circuits
- Quantum Simulation
Background:
- Qubits (two-level systems) are fundamental to quantum computing.
- Qudits (d-level systems) offer potential for enhanced computational power and richer simulations.
- Superconducting circuits are a leading platform for realizing quantum information processors.
Purpose of the Study:
- To demonstrate the operation and control of a superconducting phase qudit with d up to 5 levels.
- To utilize the qudit for emulating quantum spin dynamics.
- To measure fundamental quantum properties such as Berry's phase and spin parity.
Main Methods:
- Fabrication and operation of a superconducting phase qudit.
- Development of techniques for manipulating and measuring qudit states, including simultaneous control of multiple transitions.
- Emulation of single spin dynamics (s=1/2, 1, 3/2) using the qudit.
- Measurement of Berry's phase and spin parity via 2pi-rotations.
Main Results:
- Successful operation of a superconducting phase qudit up to d=5.
- Demonstrated precise control and measurement of the qudit state.
- Accurate emulation of spin dynamics and measurement of Berry's phase and spin parity for various spin values.
- Validation of the qudit's capability for quantum simulations.
Conclusions:
- Multilevel superconducting phase qudits are a viable extension of qubits for quantum information processing.
- Qudits provide a powerful tool for simulating complex quantum systems and exploring fundamental quantum mechanics.
- This work paves the way for more advanced quantum computational architectures and simulations.
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