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Geometric property of off resonance error robust composite pulse
Shingo Kukita1, Haruki Kiya2, Yasushi Kondo2
1Department of Physics, Kindai University, Higashi, Osaka, 577-8502, Japan. toranojoh@phys.kindai.ac.jp.
Scientific Reports
|June 10, 2022
Summary
Composite pulses (CPs) suppress errors in quantum operations. This study reveals that Off-Resonance Error (ORE) robust CPs exhibit a geometric property related to Bloch sphere trajectories, similar to Pulse Length Error (PLE) robust CPs.
Area of Science:
- Quantum Information Science
- Quantum Control
- Quantum Computing
Background:
- Quantum operations are susceptible to systematic errors, impacting precision.
- Composite pulses (CPs) are sequences mitigating these errors, widely used in Nuclear Magnetic Resonance (NMR).
- Two primary errors in one-qubit operations are Pulse Length Error (PLE) and Off-Resonance Error (ORE).
Purpose of the Study:
- To investigate the geometric properties of Off-Resonance Error (ORE) robust composite pulses (CPs).
- To demonstrate that ORE robust CPs share a simple geometric characteristic.
- To explore this geometric property using specific examples of ORE robust CPs.
Main Methods:
- Analysis of the geometric properties of ORE robust CPs.
- Mapping the trajectories of corresponding quantum operations on the Bloch sphere.
- Case studies involving two distinct examples of ORE robust CPs.
Main Results:
- ORE robust CPs possess a discernible geometric property.
- This property is intrinsically linked to the trajectories traced on the Bloch sphere.
- The geometric characteristic is analogous to that found in PLE robust CPs.
Conclusions:
- A unifying geometric perspective exists for robust composite pulse design.
- Understanding these geometric properties can enhance the development of precise quantum operations.
- The findings contribute to the broader field of quantum error suppression techniques.
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