Case study: materials
Diamonds are a physicist’s best friend
Julianna Photopoulos talks to Pascal Gallo, co-founder and chief executive of Swiss start-up company LakeDiamond, about his career in quantum physics and c r y s t a l g r ow t h i a m o n d
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Pascal Gallo is a physicist who has had a passion for crystals and gemstones since childhood, thanks to his grandfather, a mine prospector in Africa who discovered the minerals marokite and gaudefroyite. As a youngster, Gallo would often gaze at the collection of minerals they had at home, and even trade precious stones in school. Today, he is the chief executive of Switzerlandbased start-up company LakeDiamond, which manufactures ultrapure diamonds that can be harnessed for various technologies – from laser-power beaming, autonomous vehicles to rapid battery charging and medical imaging.
Gallo’s initial interest in physics was piqued by reading Stephen Hawking’s A Brief History of Time, and by having developed a strong set of strong mathematical skills. He graduated from the National Institute of A pp l i e d S c i e n c e s ( I NSA) i n To u l o u s e , F r an c e , with a Master’s degree in engineering physics and management in 2002. “This engineering school had a branch dedicated to physics, but we would also learn law, finance and economy,” he recalls.
Growing crystals Gallo continued his studies at the INSA and earned his PhD on quantum physics and crystal growth in 2006. “My PhD focused on spin dynamics – how the spin of electrons will evolve during transport within materials. And to test those properties, we needed to grow pure semiconductors by a technique called molecular-beam epitaxy,” he says. Gallo’s research was carried out in c o l l ab o r a t i o n w i t h A l b e r t F e r t who s ha r e d t h e 2007 Nobel Prize for Physics for his work on
Shine bright Pascal Gallo co - f ounded a company t o manufac t ur e diamonds f or use in t echnolog y.
spintronics. After his PhD, Gallo then spent around half a year working at the Laboratory for Analysis and Architecture of Systems, also in Toulouse, where his research involved developing new semiconductor lasers, before joining Eli Kapon’s research group at the Ecole Polytechnique Fédérale de Lausanne (EPFL) in Switzerland, later that same year, as a postdoc.
Over the next six years, Gallo worked on the interactions between light and matter in s em i c o ndu c t o r nan o s t r u c t u r e s , a t E P F L . Du ring that time, he developed diamond-based lasers and smashed a world record for laser-energy transmission. “We developed a certain class of lasers called VCSELs [vertical-cavity surface-emitting lasers], and we got a world record by putting diamonds in the cavity of those lasers,” explains Gallo. “Diamond is the best conductor of heat, so whe n y o u e v a c ua t e t h e h e a t y o u c an i n c r e a s e the power without destroying your laser.”
It was shortly after this breakthrough that Gallo had the idea to launch a star t - up company. He was, however, disappointed that he couldn’t find a good supply of ultrapure d i amond s . “ T h e r e wa s n o r e l i ab l e s o u r c e an d so we had two options: either drop the project or manufacture our own diamonds.” It wasn’t until 2011, when he met his business partner Theophile Mounier (LakeDiamond’s current chief financial officer) and the company NeoCoat, that together they developed both a single-crystal chemical vapour deposition reactor to grow artificial diamonds and a business plan for what would become LakeDiamond.
Starting up Between 2012 and 2014 Gallo worked with Kapon at BeamExpress, a Swiss start-up company that made ultrafast lasers for telecommunications. Among his duties as a research engineer and operation planner was to organize, plan and set up research projects with business partners and customers. He then worked at photonics start-up company Novagan as chief business
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