Lithium niobate as well as lithium tantalite are well established materials in optical application and radio-frequency filtering. Lithium niobate tantalate (LNT) mixed crystals are a promising material for a wide range of applications in optoelectronics due to their outstanding nonlinear optical properties. In our latest study, we focused on the targeted modification of the domain structure in LNT. Using a second-harmonic microscope, we were able…

How do lasers work? What characterises them? And what are they used for? These and other questions are addressed at the annual MINT-EC Camp at St Xaver's Grammar School in Bad Driburg. Interested pupils from all over Germany spend a whole week studying the physics of lasers. The programme also included a visit to the University of Paderborn. After an introductory lecture on how lasers work, the participants were able to gain an insight into…

For the second time, the workshop ‘PHOTONICS FUTURE. Profound | Equal | Inclusive’ took place in Bad Driburg, organised by TRR 142 and the Institute for Photonic Quantum Systems (PhoQS). It was an inspiring event that took an in-depth look at current developments in photonics as well as topics such as diversity and equal opportunities. The event was characterised by specialist presentations and stimulating discussions led exclusively by female…

Thanks to the support of TRR 142, Nina Lange had the opportunity to attend the Quantum 2.0 conference. The conference took place from 23 to 27 June in Rotterdam, the Netherlands. The aim of this of this annual conference is to bring together all types of researchers working in the field of quantum science and technology. Paderborn University was with a total of four members of the Mesoscopic Quantum Optics Working Group (Prof Dr Tim Bartley) and…

The authors theoretically investigate strategies for the deterministic creation of trains of time-bin entangled photons using an individual quantum emitter described by a Λ-type electronic system.

Physicists at Paderborn University have used complex computer simulations to develop a new design for significantly more efficient solar cells than previously available. A thin layer of organic material, known as tetracene, is responsible for the increase in efficiency. The results have now been published in the renowned journal "Physical Review Letters".

Topological states have shown prospect for bringing topological robustness into various applications and have been widely investigated in different physical systems and diverse types of lattice structures. Recently, Tobias Schneider and co-authors proposed a new type of lattice that contains two coupled cosinusoidal modulated potential chains (double-wave chains) as represented in (a) for the study of topological states in a planar semiconductor…

On-demand generation of high-quality photon states is key for implementing quantum information processing protocols. For high brightness deterministic photon sources, such as semiconductor quantum dots placed inside an optical resonator, emitter re-excitation is one of the problems undermining the quality of generated photons.

On 7 and 8 December 2023, Paderborn University hosted the 9th international workshop on Engineering of Quantum Emitter Properties (EQEP).

Scientists at Paderborn University are working with Atrineo AG to set up an extracurricular meeting and educational centre for quantum technologies as part of the joint project "Introducing Generation Z to the quantum physics mindset" (HedwiQ). The so-called Generation Z predominantly refers to young adults who were born between 1997 and 2012. The project, which is being funded by the Federal Ministry of Education and Research (BMBF) for a period…

Quantum emitters that produce both indistinguishable and polarization-entangled photons are essential prerequisites for photon-based quantum information processing.

With over ninety participants from the various TRR 142 scientific groups, this year's TRR 142 workshop was the largest to date. On 6 + 7 November 2023, the scientists presented their research results from the past year and exchanged ideas with invited guest scientists on the latest developments in the field of nonlinear photonics.

From 1 January 2024, Prof Dr Thomas Zentgraf will be the new spokesperson of the CRC TRR 142. The TRR 142-management board unanimously elected the experienced and renowned researcher in the field of ultrafast nanophotonics at Paderborn University (UPB).

Am 10. und 11. Oktober fand erstmalig die Quantum Effects statt. Mit mehr als 2000 Besucher*innen war die Premiere der Fachmesse für Quantentechnologien ein voller Erfolg. An zwei Messetagen waren auf dem Gelände der Messe Stuttgart mehr als 70 Ausstellende vor Ort. Begleitet wurde die Messe von einem Rahmenprogramm aus fachwissenschaftlichen Vorträgen, Expertendiskussionen und Workshops für Schüler*innen. So diente die Fachmesse nicht nur einer…

A constantly changing world requires profound scientific and technological knowledge. And science does not need international or gender boundaries. Therefore, we need to work hard on excellent research in an inclusive environment. On September 19 and 20, 2023, young scientists of the CRC TRR 142 and guests were invited to present their current research as well as to reflect on career paths within sciences – and what it needs to overcome our…

In einem sehr anschaulichen Video zeigt Nina Lange, wie Laserlicht einer gewünschten Farbe erzeugt werden kann. Über den sogenannnten Prozess der Summenfrequenzerzeugung wird in einem nichtlinearen Wellenleiter Licht generiert, das die für weiterführende Experimente geforderte Wellenlänge aufweist. Der Beitrag wurde auf den Social Media-Kanälen der Arbeitsgruppe Mesoskopische Quantenoptik veröffentlicht und kann zum Beispiel über diesen Link auf…

On August 3, 2023, Dr. Alexander Trautmann successfully defended his dissertation on: „Microscopic analysis of the nonlinear optical response of semiconductors: Carrier dynamics in extremely intense Terahertz fields and many-body correlations in type-II heterostructures”. Congratulations, Alexander!

Imagine two photons, the smallest quanta of light, meeting at a glass plate which transmits 50% of the light and reflects the other 50%. These two photons can take 4 different paths; either both photons are reflected or transmitted or one photon is reflected and the other one transmitted or vice versa.