Ultrafast laser plasma doping (ULPD) is a new technique developed by us to fabricate planar waveguides on glasses and silica on silicon. In this process femtosecond lasers with pulse duration <100 fs is used to ablate a target material containing ions that introduce refractive index increase as well as those suitable for light amplification such as Er3+ and Tm3+. The ablated target materials are allowed to impact on glass substrates under specific processing conditions inside a vacuum chamber leading to formation of a waveguiding layers within the subsurface of the substrate with refractive index increase as high as 10%.
The rare earth doped and undoped planar waveguide layer can be fabricated on a single substrate using this method. The Er3+/Yb3+- ions doped glass-modified-silica, and silica-on-silicon waveguides demonstrate well-defined homogeneous waveguiding layer without clustering and crystallization. This paper summarises the current state of ultrafast laser plasma doping technique, which is promising for active and passive waveguide integration on the same substrate.
Prof. Jose’s research interests are in the areas of Photonic Biosensors, photonic glasses, femtosecond pulsed laser deposition and plasma implantation, and planar waveguide devices on glass, silicon and polymer platforms. He is currently leading a £5M EPSRC-UK functional materials manufacturing research project for developing the ultrafast laser plasma doping (ULPD) process that I invented for application in advanced integrated photonics for optical data communication and sensing (www.seamatics.org). Glasses and semiconductors functionalised using ULPD are attractive for non-invasive quantum optical biosensing, integrated photonics, anti-counterfeiting/printing in glass bottles and toughening of glass for displays. He is also leading an £1.7M ESPRC Healthcare Technology project on unpconversion nanoparticles for photonic bio-sensing and imaging. He is a cofounder of a spinout company Optimus Vitrum Ltd (www.op-vi.com) which is focusing on stronger mobile screen engineering. A number of researchers and industrial partners are involved in these research and development activities of his group. I have 4 filed/granted patents and 100+ publications and his group have won Royal Academy of Engineering Entrepreneurship Award (2015), RSC emerging technologies award (2015) and Medipex- NHS innovation Award (2015). Prof. Jose received my MSc and PhD degrees in Physics from University of Calicut, India and Mahatma Gandhi University, India respectively. He was a research fellow at the Polytechnic of Milan, Italy during 2001-2002. In 2003 he joined the Department of Physics, Indian Institute of Technology Guwahati and was a Senior Lecturer/Assistant Professor there until 2007. In 2007, I joined School of Chemical and Process Engineering, University of Leeds, UK and since March 2013 he is a Professor and Chair in Functional Materials there.