A highly efficient photodetector for squeezed light measurement in the gigahertz range

verfasst von
Dennis Wilken, Jonas Junker, Michèle Heurs
Abstract

Squeezed light plays a crucial role in state-of-the-art quantum metrology and quantum information experiments. There is significant interest in utilizing squeezed states at high MHz and GHz frequencies. However, past efforts to build suitable photodetectors at these frequencies have yet to yield the required high quantum efficiency. Here, we present the development of a high-frequency balanced photodetector with near-unity quantum efficiency, realized with off-the-shelf components. The detector operates in balanced mode up to approximately 500 MHz, above which the differential frequency response limits its performance. To obtain high sensitivity above 500 MHz, the detector can be efficiently used in an unbalanced homodyne detection scheme. We employ our detector in this unbalanced mode to measure a squeezing comb up to 6.4 GHz, achieving a squeezing level of up to 10.7 dB. By sharing our experience, specifically in identifying the unequal frequency response as a limiting factor, we aim to enable and advance further developments in the field.

Organisationseinheit(en)
Institut für Gravitationsphysik
Externe Organisation(en)
Technical University of Denmark
Deutsches Elektronen-Synchrotron (DESY)
Typ
Artikel
Journal
Applied physics letters
Band
127
ISSN
0003-6951
Publikationsdatum
06.10.2025
Publikationsstatus
Veröffentlicht
Peer-reviewed
Ja
ASJC Scopus Sachgebiete
Physik und Astronomie (sonstige)
Elektronische Version(en)
https://doi.org/10.1063/5.0290396 (Zugang: Offen)