Testing a 10 micron HgCdTe detector for ground-based exoplanet science

HgCdTe detectors with longer wavelength cutoffs were created for extending the lifetime of space-based applications because of their higher operating temperatures compared to arsenic doped silicon (Si:As) detectors. In addition to lower dark currents, the HgCdTe detectors also have higher quantum efficiencies compared to Si:As detectors. We are testing a HgCdTe detector with a 12.8 micron cutoff presented in Cabrera et al 2019 using HAWAII electronics in fast read-out mode to understand this array’s viability in instruments behind future ELT s that will directly image Earth-like planets. An f/100 system is required to operate the detector on a thirty meter diameter telescope without saturating, therefore we are the same f# system on the modified cryostat used to test and characterize the detector. We will present initial results on the detector’s quantum efficiency from 2 to 12 microns, read noise, dark current, and ability to tolerate flux levels that would be seen on future ELTs.