Skip to main content
Skip to main content

Theoretical Quantum Optics

Research Group for Quantum Information and the theory of Open Quantum Systems headed by Prof. Dr. Otfried Gühne and Prof. Dr. Stefan Nimmrichter

Emmy Noether Campus

Our research profile

Our research group focuses on foundational questions in quantum information and open quantum systems. A first major topic is the phenomenon of quantum entanglement between two or more particles. Here, we are developing analytical approaches to characterize the different forms of entanglement and their usefulness.

A second major topic is quantum thermodynamics. There, we extend and refine the thermodynamical laws using tools from quantum optics and information theory in order to understand how microscopic quantum systems exchange heat, work, and information with their environment. 

Third, we are developing methods to analyze and improve quantum information processing devices using tools like shadow tomography or error mitigation.

In this research, the group forges a bridge from advanced mathematical methods to collaborations with experimentalists. We work closely with other groups doing quantum science at the University of Siegen. In addition, we collaborate with many partners around the world, e.g., from Austria, Brazil, China, France, Poland, Spain, and Sweden.

Main research areas

  • Multi-particle Entanglement
  • Graph States and the Stabilizer Formalism
  • Theory of Measurements in Quantum Mechanics
  • Open Quantum Systems
  • Bayesian Metrology
  • Shadow Tomography

Our courses

We offer various lectures and courses for the Bachelor's degree program in Physics, the Master's degree program in Physics, and the Master's degree program in Quantum Science program. The courses of the current semester can be viewed and booked on unsiono and can be booked. The regularly offered courses are

  • Introduction to Quantum Theory
  • Concepts of Quantum Science
  • Quantum Thermodynamics
  • Key Concepts of Theoretical Physics
  • Foundations of Quantum Mechanics
  • Quantum Information Theory
  • Machine Learning
Chau Nguyen

PD Dr. Chau Nguyen

Temporary Academic Councillor
Personal profile photo

Ph.D. Ismaël Septembre

Research assistant
Personal profile photo

Dr. Giulio Gasbarri

Wissenschaftlicher Mitarbeiter
Personal profile photo

Dr. Raphael Mothe

Humboldt Research Fellow (Postdoc)
Kenneth Goodenough

Kenneth Goodenough

Scholarship holder (AvH Scholarship)
Albert Rico

Albert Rico

Wissenschaftlicher Mitarbeiter
Lisa Weinbrenner

Lisa Teresa Weinbrenner

Doctoral candidate
Siyuan Qi

Siyuan Qi

Doctoral candidate
Personal profile photo

Adam Fredriksson

Doktorand

Our publications

Show more filters
A. Ketterer, S. Imai, N. Wyderka, O. Gühne

Statistically significant tests of multiparticle quantum correlations based on randomized measurements

T. Kraft, C. Spee, X.-D. Yu, O. Gühne

Characterizing quantum networks: Insights from coherence theory

Y. Dai, Y. Dong, Z. Xu, W. You, C. Zhang, O. Gühne

Experimentally Accessible Lower Bounds for Genuine Multipartite Entanglement and Coherence Measures

O. Gühne, Y. Mao, X.-D. Yu

Geometry of faithful entanglement

R. Uola, A.C.S. Costa, H.C. Nguyen, O. Gühne

Quantum steering

H.C. Nguyen, O. Gühne

Some Quantum Measurements with Three Outcomes Can Reveal Nonclassicality where All Two-Outcome Measurements Fail to Do so

X.-D. Yu, T. Simnacher, N. Wyderka, H.C. Nguyen, O. Gühne

A complete hierarchy for the pure state marginal problem in quantum mechanics

A. Ketterer, N. Wyderka, O. Gühne

Entanglement characterization using quantum designs

S. Milz, C. Spee, Z.-P. Xu, F.A. Pollock, K. Modi, O. Gühne

Genuine multipartite entanglement in time

T. Kraft, S. Designolle, C. Ritz, N. Brunner, O. Gühne, M. Huber

Quantum entanglement in the triangle network

Björn Schrinski, Stefan Nimmrichter, Klaus Hornberger

Quantum-classical hypothesis tests in macroscopic matter-wave interferometry

C. Spee, C. Budroni, O. Gühne

Simulating extremal temporal correlations

Postal address

University of Siegen
Department of Physics
Emmy-Noether-Campus
Walter-Flex-Straße 3
57072 Siegen
Germany

Visitor address

University of Siegen
Department of Physics
Emmy-Noether-Campus, Room B-107
Walter-Flex-Straße 3
57072 Siegen
Germany

Secretariat

You can find the contact details of the group members in the team overview.