Laboratory demonstration of a Photonic Lantern Nuller in monochromatic and broadband light
Journal of Astronomical Telescopes, Instruments, and Systems(2024)
摘要
Photonic lantern nulling (PLN) is a method for enabling the detection and
characterization of close-in exoplanets by exploiting the symmetries of the
ports of a mode-selective photonic lantern (MSPL) to cancel out starlight. A
six-port MSPL provides four ports where on-axis starlight is suppressed, while
off-axis planet light is coupled with efficiencies that vary as a function of
the planet's spatial position. We characterize the properties of a six-port
MSPL in the laboratory and perform the first testbed demonstration of the PLN
in monochromatic light (1569 nm) and in broadband light (1450 nm to 1625 nm),
each using two orthogonal polarizations. We compare the measured spatial
throughput maps with those predicted by simulations using the lantern's modes.
We find that the morphologies of the measured throughput maps are reproduced by
the simulations, though the real lantern is lossy and has lower throughputs
overall. The measured ratios of on-axis stellar leakage to peak off-axis
throughput are around 10^(-2), likely limited by testbed wavefront errors.
These null-depths are already sufficient for observing young gas giants at the
diffraction limit using ground-based observatories. Future work includes using
wavefront control to further improve the nulls, as well as testing and
validating the PLN on-sky.
更多查看译文
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要