Company Leadership
Jonathan Charak
Chief Executive Officer
Jonathan Charak
Jonathan is an experienced operating executive with a successful track record of leading multiple organizations through significant growth stages and high value liquidity events. His broad base of industry experience includes high tech, telecom, SaaS, and Internet of Things, and he understands the unique needs of businesses at each critical stage of its life cycle, having served in leadership roles with angel-funded pre-revenue start-ups, VC/PE owned early-stage ventures, and middle market publicly traded companies. Jonathan began his career as a practicing CPA for Arthur Andersen LLP where he performed audits for and consulted with early stage and middle market companies. Jonathan received a BS in Accounting from Indiana University Kelley School of Business.
Timothy Grotjohn, Ph.D.
Co-Founder, Chief Technology Officer
Timothy Grotjohn, Ph.D.
Timothy is a Professor of Electrical and Computer Engineering at Michigan State University (MSU) where he works on diamond process and device R&D. He joined MSU in 1987 and served for 9 years as the Department Chairperson and for six years as the R&D Director of the Fraunhofer USA Center for Coatings and Diamond Technologies located at MSU. His current research activities include diamond deposition reactor design; diamond process R&D for doped and undoped diamond; and diamond device R&D including diodes, transistors, quantum sensors and high energy particle detectors. He holds 13 patents with 9 related to diamond synthesis and processing. He has a total of 67 journal papers and over 250 conference papers/presentations. Tim received his Ph.D. in Electrical Engineering from Purdue University.
Kadek Hemawan, Ph.D.
Vice President of Production
Kadek Hemawan, Ph.D.
Dr. Hemawan currently serves as Vice President of Production at GLCT and manages DIU/NSIC projects focused on scaling manufacturing. Prior to joining GLCT, Kadek was a post-doc and a research scientist at Carnegie Science, Department of Earth and Planet Laboratory, research scientist at George Washington University, staff scientist at General Micro Systems, and director of R&D, Head of Technology Development at Snow Diamonds FD3M. Kadek also has experience as a technical consultant in companies such as Washington Diamonds, Diamond Technology Innovations, and Angstrom Materials Processing.
Paul Quayle, Ph.D.
Vice President of Research and Development
Paul Quayle, Ph.D.
Paul leads GLCT’s diamond materials and device R&D activities and is the Principal Investigator (PI) on multiple federal funding grants won by GLCT. He also has led the establishment of GLCT’s diamond manufacturing pilot line. He worked as a postdoctoral researcher advancing the manufacturing technology for diamond materials in GLCT co-founder Prof. Grotjohn’s group at MSU before joining GLCT, and he has three years of prior experience as a research scientist at Kyma Technologies. Paul received his Ph.D. in Condensed Matter Physics from Case Western Reserve University.
Debarati Mukherjee, Ph.D.
Vice President of Product Development
Debarati Mukherjee, Ph.D.
Dr. Debarati Mukherjee is Vice President of Product Development at Great Lakes Crystal Technologies, leading commercialization of single-crystal CVD diamond products. Her expertise spans diamond growth, characterization, and applications, with a strong record in improving reactor yield and enabling sub-500 °C diamond deposition.
She previously held senior research roles at Instituto de Telecomunicações, Portugal, advancing diamond integration for sensing and power electronics, and served as an Associate Editor at Nature Communications, Germany. Originally from India, she has lived and worked in five countries. She holds a PhD from Universidade de Aveiro, a Master’s from Amity University, and a Bachelor’s from St. Xavier’s College
