Quantum computers that are “practically useful” are 5-to-10 years away, Google Chief Executive Officer Sundar Pichai said, comparing the groundbreaking technology to where artificial intelligence was about a decade ago.

Google aims to release commercial quantum computing applications within five years, Google's head of quantum told Reuters on Wednesday, in a challenge to Nvidia's predictions of a 20-year wait.

Google claims quantum computing could see real-world applications within five years, sparking debate among experts worldwide.