Boston Chapter of the IEEE Photonics Society

Abstract:  Reconfiguring, modulating and processing light at visible wavelengths typically requires complex and bulky table-top optics. High resolution optical applications such as optogenetic neural studies, fluorescence microscopy, and quantum information systems have a growing need for compact and efficient platforms that can control and readout large numbers of optical channels. However, in the visible wavelength range, where key optical transitions lie, this is a significant challenge because the traditional silicon photonics chip-scale platforms cannot be leveraged due to fundamental material absorption limits. Silicon nitride has been demonstrated as a foundry-compatible, low-loss photonic platform operating down to 400 nm wavelength through optimized fabrication processes and mode engineering. This talk will highlight recent work in visible photonic integrated circuits based on silicon nitride including switching networks, optical phased arrays, chip-scale lasers, modulators and ongoing challenges for their practical application in neuroscience, imaging, and quantum systems. Finally, opportunities in mode-multiplexing and hybrid integration of active optical materials will be discussed for expanding the platform’s functional capabilities.

Biography:  Aseema Mohanty is the Clare Boothe Luce Assistant Professor in Electrical and Computer Engineering at Tufts University. She received her B.S. degree from the Massachusetts Institute of Technology and Ph.D. from Cornell University. During her postdoctoral work at Columbia University, she developed an implantable neural probe based on visible photonic integrated circuits for sub-millisecond and single-cell neural stimulation and readout. Her research focuses on using nanophotonics and engineered light-matter interactions to create miniaturized high performance optical circuits to control, shape, and sense light. Her interest in chip-scale optical devices broadly span the fields of neuroscience, implantable and wearable biomedical sensors, 3D optical beam shaping, quantum information and emerging computing and communication systems. Her work has been published in Nature Photonics, Nature Biomedical Engineering, Nature Communications and was named a Scialog fellow for Advancing BioImaging in 2021.

Location:  MIT Lincoln Laboratory Forbes Road