Jonas is an Associate Professor at the Macquarie University Centre for the Health Economy (MUCHE) with a focus on mental health and the study of older adults and ageing. He was previously a Senior Research Fellow at the Centre for the Business and Economics of Health at the University of Queensland, a researcher at the Joint Research Centre of the European Commission, and a Senior Associate at KPMG. His research aims to enable healthcare organisations to introduce new and review existing policies and programs to deliver healthcare efficiently, effectively, and equitably.

His research is at the intersection of health, economics, and psychology, he regularly works in interdisciplinary teams from those three disciplines and with other clinical researchers. Two of his primary research interests are the role of health as a determinant of economic productivity, for example, how stress and the management of stress affects worker performance, and the study of economic decisions of older adults.

Jonas has published  in many of the leading outlets for research in health economics and at the intersection of economics and psychology, including in Health Economics, Social Science & Medicine, the Journal of Public Economics, the European Journal of Health Economics, the Journal of Economic Psychology, the Journal of Behavioral and Experimental Economics, and Economics and Human Biology. He has attracted about A$4 million in external funding as a Chief Investigator or Associate Investigator on grants and fellowships.