Hardware Compatibility: Quantum computers have unique hardware requirements and operate on a different computing model compared to classical computers. Integrating quantum and classical systems requires addressing compatibility challenges and developing interfaces that enable seamless communication between the two.
Qubit Readout and Error Correction: Quantum computers are prone to errors due to decoherence and noise. Designing effective error correction techniques and readout mechanisms that integrate with classical computing systems is essential for achieving reliable and accurate results.
Opportunities:
Speedup for Specific Problems: Quantum computers have the potential to solve certain problems exponentially faster than classical computers. By integrating quantum subroutines into classical algorithms, hybrid algorithms can harness this speedup for specific tasks, leading to significant performance improvements.
Optimization and Search: Quantum computing can provide more efficient solutions for optimization and search problems. Hybrid algorithms can exploit the quantum systems' ability to explore large solution spaces and combine it with classical techniques for more effective problem-solving.
Design hybrid algorithm
Divide-and-Conquer: Break down a problem into subtasks and determine which parts can be solved more efficiently using quantum algorithms. Combine these quantum subroutines with classical algorithms to solve the overall problem.
Variational Quantum Algorithms: Utilize classical optimization methods to tune the parameters of a quantum circuit, iteratively improving its performance. This hybrid approach can enhance the efficiency of optimization tasks.
Quantum computers might soon beat ordinary ones at useful tasks, such as calculating materials’ properties. In a benchmark experiment, IBM’s quantum processor simulated the behaviour of a magnetic material. Crucially, the system managed to work around quantum noise — a major obstacle to reliable results — using an error-mitigation strategy instead of an error-correcting one. Although the experiment used a much-simplified, unrealistic model of a material, “it makes you optimistic that this will work in other systems and more complicated algorithms”, says physicist John Martinis...
Classical and quantum computing can be integrated and used together in several ways.
Hybrid computing: One way to integrate classical and quantum computing is by using a hybrid approach, where classical computers handle certain tasks and quantum computers handle others. This allows for the strengths of both types of computers to be utilized in a complementary way.
Quantum-assisted optimization: Quantum computing can be used to speed up optimization problems that are typically solved using classical algorithms. By using quantum computing to find the global minimum of a function, classical computing can then be used to refine the solution and find the local minimum.
Quantum error correction: Classical computing can be used to detect and correct errors in quantum computations. By using classical algorithms to check the results of quantum computations, the accuracy of the quantum computations can be improved.
Quantum-assisted machine learning: Quantum computing can be used to speed up the training of machine learning algorithms. By using quantum computing to find the optimal parameters for a machine learning algorithm, classical computing can then be used to apply the algorithm to new data.
Quantum key distribution: Classical computing can be used to encrypt and decrypt messages using quantum key distribution. By using quantum computing to generate and distribute encryption keys, classical computing can then be used to encrypt and decrypt messages.
Quantum simulation: Quantum computing can be used to simulate quantum systems that would be impossible to simulate using classical computing. By using quantum computing to simulate quantum systems, classical computing can then be used to analyze the results of the simulation.
Quantum cryptography: Classical computing can be used to encrypt and decrypt messages using quantum cryptography. By using quantum computing to generate encryption keys, classical computing can then be used to encrypt and decrypt messages.
Quantum hardware-software co-design: Classical computers can be used to design and optimize quantum hardware, and quantum computers can be used to design and optimize classical software...