Advancing a novel brain imaging method
VCSEL arrays with record high modulation bandwidth
Catherine Best’ s team performed the first-ever high-resolution imaging of the mouse brain using spatial light interference microscopy.
Advancing a novel brain imaging method
Research Assistant Professor Catherine Best and MNTL affiliate faculty member Gabriel Popescu led a team of researchers that performed the first-ever high-resolution imaging of the mouse brain using spatial light interference microscopy( SLIM). A quantitative imaging technique, SLIM had previously only been used to image single neurons in the mouse brain. Unlike other imaging methods that require fluorescent dyes that limit their use to rodent models, SLIM can provide unprecedented quantitative cytostructural information across multiple regions in the brain at the anatomical level for multiple animal brain models. In addition, the technique provides Corpus callosum fiber angle of orientation in coronal and sagittal sections. Best’ s results indicate that, in principle, SLIM can computationally produce a 3D rendering of the entire mouse brain, which would enable researchers to observe all the brain connections from the nanometer to centimeter scale.
Source: Scientific Reports,“ Label-free, multi-scale imaging of ex-vivo mouse brain using spatial light interference microscopy,” December 23, 2016.
VCSEL arrays with record high modulation bandwidth
The data rate for optical digital communication systems continues to increase to satisfy the demands of the Internet. This in turn requires continual improvement of the semiconductor optical device technologies that are used in digital interconnects. For short distance interconnects, the dominant laser source is the vertical cavity surface emitting laser( VCSEL), an optoelectronic technology that ECE Professor Kent Choquette and his Photonic Device Research Group have pursued for more than two decades. Recently Choquette’ s group has developed optically coupled photonic crystal VCSELs that exhibit record high modulation bandwidth. By using two optically coupled VCSELs that emit coherently, the modulation bandwidth which previously was less than 30 GHz from a single laser, has been increased to nearly 40 GHz, which will enable a significant increase in the data rate. These coherent laser arrays also have improved output power and significantly reduced emission linewidth, which are critical parameters for optical interconnects.
Source: Proceedings SPIE,““ Low dispersion ultrahigh bandwidth vertical cavity surface emitting laser arrays,” March 18, 2016.
A top view of a photonic crystal VCSEL array fabricated by Professor Kent Choquette’ s Photonic Device Research Group.
MNTL | 4 | University of Illinois at Urbana-Champaign