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Dynamical generation of noiseless quantum subsystems
1d'Arbeloff Laboratory for Information Systems and Technology, Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Physical Review Letters
|October 13, 2000
Summary
We developed a method combining quantum control and coding to protect quantum systems from noise. This allows for universal quantum computation even with limited resources and arbitrary linear noise.
Area of Science:
- Quantum Information Science
- Quantum Control Theory
- Quantum Error Correction
Background:
- Open quantum systems are susceptible to noise, hindering reliable quantum computation.
- Existing methods for noise protection often require significant control resources or are limited in scope.
Purpose of the Study:
- To develop a unified framework for universal quantum control of open quantum systems.
- To engineer noise-protected subsystems using coding procedures and dynamical decoupling.
- To demonstrate the feasibility of quantum computation in the presence of arbitrary linear quantum noise.
Main Methods:
- Combining dynamical decoupling techniques with universal control strategies.
- Employing a general algebraic approach for state encoding.
- Utilizing two-body Hamiltonians for constructing quantum gates.
Main Results:
- Achieving universal control over dynamically generated noise-protected subsystems.
- Demonstrating that appropriate state encodings enable robust quantum computation.
- Developing a constructive scheme for universal quantum computation over large noiseless spaces.
Conclusions:
- The proposed method offers a powerful approach to building fault-tolerant quantum computers.
- This technique allows for efficient quantum computation despite environmental noise.
- The framework is applicable to systems with arbitrary linear quantum noise and limited control resources.
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