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Quantum Error-Correction-Enhanced Magnetometer Overcoming the Limit Imposed by Relaxation.
David A Herrera-Martí1, Tuvia Gefen1, Dorit Aharonov2
1Racah Institute of Physics, The Hebrew University of Jerusalem, Jerusalem 91904, Givat Ram, Israel.
Physical Review Letters
|November 28, 2015
Summary
Quantum error correction can overcome relaxation limits in quantum sensors. A new superconducting magnetometry design uses this to extend coherence times beyond fundamental limits.
Area of Science:
- Quantum sensing
- Quantum error correction
- Superconducting circuits
Background:
- Relaxation limits sensitivity in quantum sensors.
- Dynamical decoupling cannot overcome relaxation limits.
- Quantum error correction is necessary to surpass relaxation limits.
Purpose of the Study:
- To present a superconducting magnetometry design.
- To incorporate approximate quantum error correction.
- To extend coherence times beyond the relaxation limit.
Main Methods:
- Utilizing approximate quantum error correction.
- Implementing a two-qubit Hamiltonian term for signal generation.
- Employing a tunable coupler between two transmon qubits.
Main Results:
- Demonstrated a method to correct for high frequency noise.
- Showcased a design that complements refocusing techniques.
- Achieved extended coherence times beyond the relaxation limit.
Conclusions:
- Quantum error correction offers a pathway to overcome fundamental sensitivity limitations in quantum sensors.
- The proposed superconducting magnetometry design effectively utilizes quantum error correction to enhance performance.
- Fast error correction is key to extending device coherence times past relaxation limits.
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