Bert Jan Offrein

University of Twente, Enschede, The Netherlands. (Since September 2021)

Professor by special appointment 'Analog Signal Processing' (in parallel to the full time appointment at IBM Research)

IBM Research Europe - Zurich, Rüschlikon, Switzerland. (Since November 1999)

Manager Neuromorphic Devices and Systems Group (Since July 2016) The group establishes novel devices and subsystems for high performance and power efficient neuromorphic computing. Special emphasis is put on AI accelerators for analog synaptic signal processing. Both electrical and photonic implementations are pursued. Electrical analog AI accelerator are based on memristive crossbar arrays while the photonic devices build on silicon photonics technology as originally established for optical communication.

Manager Photonics Group (October 2004 - June 2016) The photonnics group addressed new technologies, materials and advanced concepts for optical interconnects, silicon photonics and nanophotonic devices.

Research Staff Member in the Photonics group (October 2002 – September 2004) Optical interconnect technology for board-level links. Focus on the integration of transceivers and the assembly of optical connectors.

Manager Photonic Device Technology group (September 2000 – September 2002) The silica-silicon photonic integrated circuits technology based on silicon-oxynitride is commercialized with an external partner. The Photonic Device Technology team designs and characterizes state of the art devices such as dynamic gain equalizers, adaptive chromatic dispersion equalizers and add-drop filters for telecommunication applications. Furthermore there is a strong focus on understanding and improving the fundamental properties of the technology.

**JDS Uniphase, Zurich, Switzerland. ** (November 1999 - Augustus 2000)

Representative product engineer / Yield engineer (December 1996 - October 1999) Customer interface for the latest 980 nm pump laser product. Yield analysis and optimization as well as parameter extraction automation to enable a transition to full 2 inch wafer processing.

**IBM Research - Zurich, Rüschlikon, Switzerland. ** (June 1995 - October 1999)

Research Staff Member in the Optical Networking group Establish silica-on-silicon integrated optic technology based on high-index contrast silicon-oxynitride. Focus on the design and characterization of dynamic optical devices.

Post Doctoral Researcher in the Optical Networking group
Establish silica-on-silicon integrated optic technology based on high-index contrast silicon-oxynitride. Focus on the design and characterization of dynamic optical devices and establishing the required measurement infrastructure.

Faculty of Applied Physics, University of Twente, the Netherlands (November 1990 - Mai 1995)

Post Doctoral researcher in the Transduction and Materials Science group (November 1994 - Mai 1995) Continuation of the PhD thesis work, perform lectures for students.

PhD Student in the Transduction and Materials Science group
(November 1990 – Oct. 1994)

PhD Thesis defense at October 28, 1994
Thesis: 'The Fabry-Perot Resonator as an All-Optical Switching Device.'
PhD Advisor: Prof.Dr. Th.J.A. Popma, Assistant Advisor: Dr. H.J.W.M. Hoekstra.
The thesis research addressed the design and realization of integrated optic Fabry-Perot resonator as an all-optical logic switch. Methods to characterize the nonlinearity of potential materials were established and tested. Nonlinear devices were realized, simulated and measured.