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100,000-spin coherent Ising machine
Toshimori Honjo1, Tomohiro Sonobe2, Kensuke Inaba1
1NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato Wakamiya, Atsugi, Kanagawa 243-0198, Japan.
Science Advances
|September 29, 2021
Summary
A new coherent Ising machine (CIM) using over 100,000 pulses solves complex optimization problems much faster than traditional methods. This quantum computing approach shows promise for machine learning applications requiring rapid random sampling.
Area of Science:
- Quantum Computing
- Computational Physics
- Optimization Algorithms
Background:
- Digital computers face performance limitations.
- Physical system-based computers offer potential solutions.
- Coherent Ising Machines (CIMs) are designed for combinatorial optimization.
Purpose of the Study:
- To report on a large-scale Coherent Ising Machine (CIM).
- To demonstrate the CIM's capability in solving complex optimization problems.
- To evaluate the CIM's performance against established algorithms.
Main Methods:
- Development of a CIM utilizing 100,512 degenerate optical parametric oscillator pulses as Ising spins.
- Testing the CIM on maximum cut problems for large-scale graphs (100,000 nodes).
- Comparison of CIM performance with standard simulated annealing algorithms.
Main Results:
- The CIM achieved significantly faster solutions for 100,000-node graph maximum cut problems compared to simulated annealing.
- Operation near the phase transition point yielded exceptionally high-quality solutions.
- The CIM demonstrated a broad solution distribution, beneficial for random sampling tasks.
Conclusions:
- The developed CIM represents a significant advancement in quantum computing for optimization.
- The machine's speed and solution quality surpass conventional methods for specific problems.
- The CIM's characteristics are highly suitable for machine learning and other random sampling applications.
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