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Size effect of high contrast gratings in VCSELs
Christopher Chase1, Ye Zhou, Connie J Chang-Hasnain
1Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, CA 94720, USA.
Abstract:
We report on the effects of shrinking the physical size of a high index contrast grating (HCG) on a vertical cavity surface-emitting laser (VCSEL). HCGs previously had been simulated assuming infinite periodicity. Here we probe through simulation and experiment the effect of reducing the HCG to only a few periods. We experimentally realize lasing VCSELs with as few as 4 periods of HCG. By shrinking the HCG to an extremely small size and integrating it on a wavelength tunable VCSEL, we are able to achieve a tunable VCSEL with a record fast mechanical tuning response of >27 MHz. This is a 5X improvement over the fastest previously reported wavelength tunable VCSELs.
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