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Updated: May 19, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Geometric aspects of composite pulses.
Tsubasa Ichikawa1, Masamitsu Bando, Yasushi Kondo
1Research Center for Quantum Computing, Interdisciplinary Graduate School of Science and Engineering, 3-4-1 Kowakae, Higashi-Osaka, Osaka 577-8502, Japan.
Summary
Composite pulses in nuclear magnetic resonance ensure reliable quantum computing by creating robust operations. These pulses, compensating for errors, act as geometric quantum gates, implementing unitary gates through holonomy.
Area of Science:
- Quantum Computing
- Nuclear Magnetic Resonance (NMR)
- Quantum Information Science
Background:
- Reliable quantum computing necessitates unitary operations robust against systematic control parameter errors.
- The composite pulse technique in NMR offers a method for achieving such robust operations using sequences of imperfect pulses.
Purpose of the Study:
- To demonstrate that specific composite pulses in NMR exhibit vanishing dynamical phases.
- To show these pulses can be interpreted as geometric quantum gates.
Main Methods:
- Investigated two types of composite pulses: one for pulse length errors in single-qubit systems and another for J-coupling errors in two-qubit systems.
- Analyzed the dynamical phase acquired by these composite pulse sequences.
Main Results:
- Demonstrated that both investigated composite pulse sequences result in a vanishing dynamical phase.
- Established a connection between these error-compensating pulses and geometric quantum gates.
Conclusions:
- Composite pulses with vanishing dynamical phases can function as geometric quantum gates.
- This finding provides a pathway for implementing robust and precise unitary operations in quantum computing.
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