Interferometry

Chenyu W Hu, Ben Wang, Jiandong Zhang +4 more

Resolving high-contrast targets is a fundamental, yet highly challenging, task in astronomy. Using quantum estimation theory, we demonstrate that the ultimate limit for estimating the separation between two unequal-brightness thermal sources via interferometry remains constant, enabling the potential for superresolution. We give a comparative analysis of two primary stellar interferometric schemes: amplitude interferometry and intensity interferometry. Notably, the nulling strategy employed in amplitude interferometry, a configuration specifically proposed for exoplanet detection by leveraging destructive interference to suppress the brighter source, is quantum optimal for separation estimation. While intensity interferometry is less effective than amplitude interferometry in lossless scenarios and fails to achieve superresolution, it becomes competitive when optical loss in large-scale interferometry is considered. By applying these methodologies to modern stellar interferometry, we highlight the promise of large-scale interferometry for advancing high-resolution astronomical observation.

Lawrence N. Mertz

M. M. Bérubé, Michael D. Mazurek, Kevin J. Resch

Chirped-pulse interferometry (CPI) is a classical low-coherence interferometry technique with automatic dispersion cancellation and improved resolution over white-light interference. Previous work showed that CPI with linearly chirped Gaussian laser pulses achieves a $\sqrt{2}$ improvement in resolution over conventional white-light interferometry, but this is less than the factor of 2 improvement exhibited by a comparable quantum technique. In this work, we show how a particular class of nonlinearly chirped laser pulses can meet, and even exceed, the factor of 2 improvement in resolution. This enhanced-resolution CPI removes the resolution advantage of quantum interferometers in dispersion-cancelled interferometry.

Lada Radmacherova

Tato práce se zaměřuje na teoretické aspekty jednofotonové interferometrie, intenzitní interferometrie a nově navržené dvouzdrojové amplitudové interferometrie, jakož i na jednofotonové detektory, které jsou klíčové pro implementaci posledních dvou metod. Dále prezentuje experimentální výsledky získané měřením pomocí LinoSPAD2 detektoru. Tyto výsledky zahrnují charakterizaci Hanbury Brown and Twiss efektu, který tvoří základ intenzitní interferometrie a dvouzdrojové amplitudové interferometrie, charakterizaci cross-talku pro LinoSPAD2 detektor a offset kalibraci LinoSPAD2 detektoru. Všechny výsledky jsou ve shodě s teoretickými předpověďmi a výzkum v oblasti kvantové astrometrie pokračuje k testům nové dvouzdrojové amplitudové interferometrie.

Matt Young