Recently, it has been shown that so-called "superconducting nanowire single photon detectors" (SNSPD) can not only provide information about the presence or absence of photons, but also resolve the number of incident photons in a laser pulse. In this work, we investigated where this photon-number information is located on the electrical output signal (trace) of the SNSPD and how it can be best retrieved in an experiment. We did this by recording…

Last week four members of our group went to the Quantum 2.0 conference in Rotterdam, Netherlands. They enjoyed a great meeting and had a lot of time to network and talk about their work. We contributed with two presentations and one poster: Timon Schapeler talked about "Photon-number resolution with SNSPDs via statistical analysis of electrical traces" Frederik Thiele talked his work about "Opto-Electronic Operation of an SNSPD with a…

Two of our group members contributed to a conference in Gaeta, Italy last week. It was a meeting of the Horizon 2020 FET OPEN project Stormytune with the name "Spectral-Temporal Metrology with Tailored Quantum Measurements". Aishi Barua presented her poster about "Investigating Homodyne Detection with Squeezed Light as the Local Oscillator". Lorenzo Procopio presented his talk about "Quantum Metrology Enhancement using Indefinite casual…

Last week three members went to the conference CLEO in Charlotte. The conference was about Lasers, electro-optics, and photonic applications. In addition, our former colleague Maximilian Protte joined us again and presented work which was realized in Paderborn. We presented our works in contributing talks and poster presentations: Niklas Lamberty: Maximizing photon-number resolution from an SNSPD Maximilian Protte: Performing Balanced…

We welcome Lorenzo M. Procopio, who joined our group as a Post Doc.  After our 7th group reflection meeting last week, we had dinner together at Mundus in Paderborn.

Last week, four members of our group attended the spring meeting of the Atoms, Molecules, Quantum Optics and Photonics Section of the German Physical Society (DPG SAMOP). The conference took place from 10th to 15th of March in Freiburg. During the conference we presented the following contributions: Niklas Lamberty - Maximizing photon-number resolution from an SNSPD (Talk) Isabell Mischke - Multiwavelength Characterization of Polarization…

We build photonic circuits for quantum optics with the material system lithium niobate. The material system enables us to realize several devices such as quantum light sources and modulators. For several applications we need to cool the material system down to cryogenic temperatures (below 10K). The challenge with photonic circuits is to maintain a high device performance at cryogenic temperatures. We managed to maintain a good performance for…

We welcome Aishi Barua as a new PhD student in our group. 

The latest episode of the "PaderPhy - Der Paderborner Physik Podcast" features Prof. Bartley. Check it out here.

We just posted a new video about our latest publication in Optica Quantum from Maximilian Protte and Timon Schapeler. In this video Maximilian talks about the experiment and the results. It can be found here, it was edited by Jessika Bruns. The original news article can be found here and the publication here.

We congratulate Isabell Mischke for successfully defending her bachelor thesis about "Broadband Characterization of Superconducting Nanowire Single-Photon Detectors".

Our former group member Maximilian Protte was awarded for an excellent dissertation at the 2024 New Year’s Reception at Paderborn University.

Have you ever thought of using superconducting single-photon detectors for homodyne detection? In our newest publication we show how we used superconducting nanowire single-photon detectors (SNSPDs) to study the continuous variables of optical quantum states using homodyne detection. From the joint click statistics of two SNSPDs we measured the phase-dependent quadrature of a weak coherent state, which was interfered with a continuous wave local…

As we are part of the Institute for Photonic Quantum Systems (PhoQS), multiple members of our group participate in the PhoQS school program. We want to raise the interest of school students in the fascinating world of physics and quantum optics. We visit physics classes of the upper school and give exclusive insights in the physics studies and what it is like to work in an academic research group. Moreover, this is a great chance for the pupils…

Yesterday we said goodbye to Max, as he will leave the group after almost five years in our group. We met in the afternoon to have eat pizza together, play games and had a lot of fun, especially at "Uno mit Zwischenlegen". Thanks for all your work, and being a big part of our group!