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Specialised QUBITS SEMINAR: Prasana Kumar Sahoo

Mon, 15 Jun 2026 14:30:00 +0200

Ole Rømer Colloquium

Brigitte Christina Henderson — Wed, 13 May 2026 14:00:00 +0200

Join us for the next Ole Rømer Colloquium where Kazimierz Rzewski, CFT PAN, Warsaw, Poland, will visit us

Specialized QUBITS SEMINAR: Krzysztof Pawlowski

Mai Korsbæk — Tue, 12 May 2026 14:00:00 +0200

Quantum Physics Talk - Frank Schlawin

Brigitte Christina Henderson — Tue, 12 May 2026 11:00:00 +0200

Speaker: Frank Schlawin, Faculty of Mathematics, Informatics and Natural Sciences, Institut für Laserphysik, University of Hamburg

Title: Quantum technologies for materials and molecularscience: opportunities for spectroscopy and control
Abstract:
Recent years have seen a remarkable convergence between nonlinear and quantum optics and the physics of quantum materials and molecular science. This development is driven by major advances in optical technology, which now enable us to probe and manipulate matter with tailored light pulses [1,2]. Such control provides powerful avenues to, for instance, manipulate nonequilibrium phases, and potentially stabilize new forms of coherent quantum matter [1]. Optical quantum technologies, such as cavity quantum electrodynamics or bright nonclassical states of light, are poised to significantly advance this field [2, 3]. They enable the creation of highly entangled light-matter hybrid states, facilitate the transfer of quantum correlations from light to matter, and improve detection sensitivity.

In my talk, I will share my perspective on these emerging developments, emphasizing how quantum technologies can open new opportunities for both spectroscopy and optical control. I will discuss how strong coupling to electromagnetic cavities can affect material properties. Additionally, I will explore how quantum states of light, originally developed for quantum information processing, may enable quantum-enhanced spectroscopy and more efficient signal extraction, ultimately paving the way for novel experimental capabilities in material and molecular science.

[1] J. Bloch, A. Cavalleri, V. Galitski, M. Hafezi, and A. Rubio, Nature 606, 41-48 (2022).

[2] K. E. Dorfman, FS, and S. Mukamel, Rev. Mod. Phys. 88, 045008 (2016).

[3] FS, D. Kennes, and M. A. Sentef, Appl. Phys. Rev. 9, 011312 (2022).

Ph.d.-forsvar: Lights, Cameras, Action! Real-Time Quantum Sensing from Few-Photon Probing to MW Polarimetry, v/Laurits Nikolaj Stokholm

Ann-Berit Porse Stærkær — Wed, 06 May 2026 14:30:00 +0200

Talk by Dr. Robert Löw, Physikalisches Institut, University of Stuttgart

Brigitte Christina Henderson — Wed, 06 May 2026 11:15:00 +0200

Abstact:

At the University of Stuttgart we have developed a new kind of setup that combines the physics of ultracold atoms or molecules with a highly spatial resolving ion microscope. This microscope delivers an optical resolution of a few 100nm with a nano-second time resolution. With this it is possible to study their spatial and electronic structure, as well the dynamics of Rydberg atom ion pairs. We have performed such experiments for bound and unbound atom-ion pairs. As a next step, we want to show that the binding mechanism between ions and Rydberg atoms is not limited to diatomic molecules but can be extended to polyatomic systems, for which we expect even more intricate interactions.

Talk by Zhanybek Alpichshev, Institute of Science and Technology Austria (ISTA)

Tue, 05 May 2026 14:15:00 +0200

Abstract:
The advancement of high-speed data processing and signal manipulation technologies has pushed the frontier into the terahertz (THz) frequency range, raising a fundamental challenge: how to efficiently control electromagnetic fields at these frequencies. This issue, often referred to as the "THz gap" in optical and electronic engineering, remains a major obstacle to practical applications. A promising strategy is to manipulate THz electromagnetic waves through polaritonshybrid light-matter excitationsthat harness the intrinsic nonlinear response of matter.

In this talk, I will introduce Quantum Paraelectric (QP) solids as a novel platform for THz phonon-polaritonics, leveraging the extreme nonlinearity of SrTiO in its QP phase, which arises due to its proximity to the incipient ferroelectric state. This strong nonlinearity enables efficient self- and cross-coupling between polaritons, paving the way for all-optical, field-programmable THz polariton circuits.

If time allows, in the second part of the talk I will turn to the basic problem of linear propagation of THz electromagnetic waves in SrTiO and KTaO. As it turns out, our experimental data challenges long-held assumptions about light propagation in dispersive dielectricsan area considered settled since the foundational works of Lorentz, Sommerfeld, and Brillouin bringing a fresh perspective on a fundamental problem in wave physics.

Distinguished Senior Innovators Programme: Evaluation and Future Opportunities

Tue, 05 May 2026 14:00:00 +0200

QUBITS SEMINAR - Dr. Emil Zanchetta Ulsig

Karin Vittrup — Mon, 04 May 2026 14:15:00 +0200

Dr. Emil Zanchetta Ulsig, Dept. of Electrical & Computer Engineering, QVersion

Quantum Physics Talk - Frederik Nathan

Brigitte Christina Harke Henderson — Wed, 29 Apr 2026 11:00:00 +0200

Speaker: Frederik Nathan, Niels Bohr Institute, University of Copenhagen
Title: Self-correcting qubits: harnessing dissipation for quantum error correction in driven-dissipative circuits

Abstract:
We propose a protocol for creating and dissipatively error-correcting a qubit encoded in the Fock space of a superconducting resonator mode. The device consists of a high-impedance LC resonator coupled to a Josephson junction and a resistor through a time-dependent switch. Controlling the switch via a particular family of stepwise protocols drives the system into a regime of completedissipative error correction, where the resistor acts as a sink for noise-induced entropy, leading it to correct both dephasing and bit-flip errors. We confirm the emergence of dissipative error correction in simulations, and show that it leads to exponential enhancement of coherence time, reaching macroscopic (+10 ms) scales for near-feasible parameters, even in the presence of extrinsic noise. The qubit supports self-correcting Clifford gates, where control noise is dissipatively corrected, leading to exponentially-scaling gate fidelity. A self-correcting non-Clifford gate can be implemented by augmenting the circuit with ancilla Josephson junctions.

Coffee and cake will be served