NIR habitable exoplanet spectroscopy with the matched electric field spectrograph (MEFS)

Direct spectroscopy of habitable exoplanets must overcome low source flux and comparatively higher background, requiring exposure times of weeks for the HWO mission. Spectroscopy in the information-rich NIR regime is particularly challenging, as poorer angular resolution exacerbates background mixing, especially near the coronagraph IWA. We propose to match the post-coronagraph exoplanet electric field to the input of a single-mode spectrograph using a photonic lantern (PL) positioned on the planet location, and feeding a photonic integrated circuit (PIC). We show that the approach offers an order of magnitude gain in exposure time, and extends exoplanet spectroscopy to the NIR regime by enabling a smaller IWA. We discuss this approach as a NIR spectroscopy module for the HWO mission, and provide an overview of ongoing technology validation activities, including on-sky demonstration of its key elements at the Subaru Telescope.