NEW DELHI: Barun Gorain joined Hindustan Zinc Ltd as chief technology and innovation officer two months ago, moving from Barrick Gold in Canada, one of the many CXO-level hires that Indian companies have been making in the buzzing areas of artificial intelligence (AI), machine learning, the Internet of things (IoT) and robotic process automation (RPA). Other recent instances of Indians returning home with domain knowledge in these emerging technologies include Raghuram Velega, who left his job at a San Francisco-based cognitive computing company to join Reliance Jio Infocomm as vice-president, head, big data and analytics. Former National Aeronautics and Space Administration (NASA) executive Santanu Bhattacharya joined Bharti Airtel as chief data scientist and Ayush Sharma moved from Silicon Valley to join Reliance Jio as senior vicepresident of engineering and technology. Search firms like Korn Ferry, EMA Partners, Transearch and Hunt Partners say there's a paucity of experts in these fields, leading to a jump in salaries of new hires by as much as 50%, most of them from overseas. Salaries for such executives are at Rs 1-2 crore annually but can be even higher.