SandboxAQ has raised over $300 million at a valuation of more than $5.6 billion, which will help the startup recruit more engineers for an effort to apply quantum technology and techniques to AI development.Chaired by former Google chief Eric Schmidt, the company was spun out from Alphabet Inc. less than three years ago and has partnerships with the likes of Accenture and Deloitte as it pursues corporate customers. Investment firm Alger and Yann LeCun are new investors participating in the lates...