Dr. Atul Gawande, an accomplished surgeon, writer and Harvard professor, has been named the chief executive officer of a new initiative started by Amazon.com Inc. , Berkshire Hathaway Inc. and J.P. Morgan Chase & Co. , with the goal of improving health care for their more than a million combined U.S. employees, as well as making it more cost-effective. Gawande’s tenure will begin July 9. The independent company will be headquartered in Boston and be “free from profit-making incentives and constraints.” “This work will take time but must be done,” Gawande said. “The system is broken, and better is possible.” Gawande is a surprising choice in many respects, as he is best known for his empathetic approach to medicine than for financial or health-care management credentials. The initiative has been expected to shake up the status quo, and even sent shares of companies across the health care industry tumbling after the late January announcement. Previous reports pegged David Feinberg, the chief executive of Geisinger Health System, as the top candidate. But the surgeon-writer may lend some credibility to the idea that any discoveries made by the health-care initiative may be shared beyond the three companies, as J.P. Morgan Chief Executive Jamie Dimon suggested in the original announcement. The Health Care Select Sector SPDR has surged 1% over the last three months, compared with a 2% rise in the S&P 500 and a 0.1% rise in the Dow Jones Industrial Average .