IQIM Postdoctoral and Graduate Student Seminar

Abstract: By computing quantum bounds for incoherent imaging, we discovered in 2015 that the fundamental resolution of optical telescopes is much higher than previously realized [1]. The discovery has inspired the invention of a quantum-limited measurement method called spatial-mode demultiplexing (SPADE), as well as 40+ experiments over the past few years [2]. Similar calculations show that, for optical phase noise spectroscopy, spectral photon counting can be far superior to homodyne detection and achieve the fundamental quantum limit [3], an idea that has recently been picked up by the GQuEST project [4]. I also discuss an old idea of backaction noise cancellation for optomechanics [5], noting its difference from the frequency-dependent squeezing method recently demonstrated in LIGO.