26/05/2026 : Serena Federico @PoliMi

Alessandro OlgiatiSeminar PoliMi 
Tuesday, May 26, 2026 - 11:00
Sala Consiglio (7th floor) - Bd. 14 "Nave", Via Bonardi 9
Politecnico di Milano

Zoom link on request (contact Alessandro Olgiati by email)

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SPEAKER: Serena Federico (University of Bologna)

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Weyl calculus on graded Lie groups

In this talk, we shall discuss the existence of a Weyl pseudo-differential calculus on a graded Lie G.
To begin with, we will introduce a family of admissible quantizations on G and develop the corresponding pseudo-differential calculus. Afterwards, following classical criteria, we shall identify the suitable candidate Weyl quantization on G among all the admissible symmetric ones. Finally, we will show that in the case of the Heisenberg group, the Weyl quantization is uniquely determined.
This talk is based on a joint work with D. Rottensteiner and M. Ruzhansky.

08/05/2026 : Yelena Guryanova @PoliMi

Alessandro OlgiatiSeminar PoliMi 
Friday, May 8, 2026 - 11:00
Sala Consiglio (7th floor) - Bd. 14 "Nave", Via Bonardi 9
Politecnico di Milano

Zoom link on request (contact Alessandro Olgiati by email)

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SPEAKER: Yelena Guryanova (University of Basel / QuantumBasel)

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Cloning Quantum Channels

For states, the no-cloning theorem is one of the first encounters in quantum information: an arbitrary unknown pure state cannot be perfectly copied onto a waiting register. It’s simple then to infer that cloning N states onto M registers won’t work either, but by relaxing the problem to allow for imperfect (approximate) copying, one can investigate the rate and quality of N-to-M cloning. But what if we go further? Can we imagine cloning the cloner, in other words, cloning devices themselves? Questions around states have constituted decades of investigation and were, most recently, extended to cloning unitary gates. In this work we pose the question comprehensively and study general quantum channel cloning via a framework based on higher-order quantum operations. We establish necessary conditions for a family of channels to exhibit super-replication—those that can be cloned with a quadratic rate at high-quality (bounded error). Noisy phase-gate channels can be super-replicated but the full set of noisy unitaries; classical noise; and amplitude damping channels cannot. We present algorithms that search for channel cloners and study specific cloning strategies. In many cases, estimating and re-preparing is enough: for the unitary gates for which super-replication protocols were known, we construct simpler alternatives and establish a direct connection between channel cloning and Bayesian estimation.

16/04/2026 : Hynek Kovařík @PoliMi

Alessandro OlgiatiSeminar PoliMi 
Thursday, April 16, 2026 - 15:30
Aula Seminari (3rd floor) - Bd. 14 "Nave", Via Bonardi 9
Politecnico di Milano

Zoom link on request (contact Alessandro Olgiati by email)

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SPEAKER: Hynek Kovařík (Università degli studi di Brescia)

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Cwikel-Lieb-Rozenblum type estimates for magnetic Hamiltonians in dimension two

In this talk I will present Cwikel-Lieb-Rozenblum type inequalities for the number of negative eigenvalues of Pauli and Schroedinger operators in dimension two. The resulting upper bounds are sharp both in the weak as well as the strong coupling limit. In both cases, the nature of the inequality depends on whether the flux of the magnetic field is integer or not. The talk is based on a joint work with Matthias Baur.

15/04/2026 : Meriem Abdelaziz @UniMi

quantumseminarSeminar UniMi 
Wednesday, April 15, 2026 - 16:15
Aula M02 - Via Mangiagalli, 31
Università degli Studi di Milano

Zoom link on request (contact Niels Benedikter by email)

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SPEAKER: Meriem Abdelaziz (University of Biskra)

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Analytical Solutions of the Schrödinger Equation for Diatomic Molecules in Deformed Spaces

In this work, we investigate the analytical solutions of the Schrödinger equation for diatomic molecular systems using the pseudo-harmonic and Kratzer potentials. The study is carried out in both standard quantum mechanics and in deformed frameworks, namely de Sitter and anti-de Sitter spaces, incorporating the effects of the Extended Uncertainty Principle (EUP). By applying the extended Nikiforov–Uvarov method, we derive explicit expressions for the energy eigenvalues and corresponding wave functions. The influence of quantum deformation on the spectral properties of selected diatomic molecules is analyzed, highlighting potential implications for quantum technologies.

Slides_AbdelazizDownload

18/03/2026 : Lorenzo Pettinari @UniMi

quantumseminarSeminar UniMi 
Wednesday, March 18, 2026 - 11:30
Aula 305 - Via Golgi 18/20 (Settore didattico)
Università degli Studi di Milano

Zoom link on request (contact Niels Benedikter by email)

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SPEAKER: Lorenzo Pettinari (University of Trento)

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Damping of phonons in Bose gas at low temperature

Condensed Bose gases can be effectively described in terms of quasi-particles, commonly referred to as phonons. Their dynamics are captured by a c-number ondensate Hamiltonian consisting of a quadratic term supplemented by third- and fourth-order perturbative corrections. These additional interaction terms render the phonons unstable, giving rise to two distinct decay processes known as Beliaev and Landau damping. From a mathematical perspective, such decay mechanisms should manifest as a broadening of the Bogoliubov dispersion relation in the thermodynamic limit. To validate this picture, I will present two different approaches to deriving the phonon decay rates. The first is inspired by the W*-algebraic framework of Jaksic-Pillet, employing Standard Representations and perturbative expansions of a suitably chosen vector state. The second method is based on the analysis of two-body correlation functions. Both approaches yield the same imaginary correction to the Bogoliubov dispersion relation, which in turn determines the expected broadening. urthermore, our approaches offer a new perspective on the decay of phonons in terms of the left and right components of these quasi-particles. The talk is based on joint work with Jan Derezi´nski and may be viewed as a modern laboration of the classical contributions of Beliaev, Hohenberg–Martin, and others.

Seminar Slides Lorenzo PettinariDownload

12/01/2026 : Ian Jauslin @UniMi

quantumseminarSeminar UniMi 
Monday, January 12, 2026 - 14:00
Aula C01 - Via Luigi Mangiagalli, 25
Università degli Studi di Milano

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SPEAKER: Ian Jauslin (Rutgers University)

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A framework to study twisted bilayer graphene in a tight binding model

The study of the electronic properties of twisted bilayer graphene (TBG) has garnered much attention from the condensed matter community recently. TBG is obtained by stacking two graphene monolayers on top of each other, and rotating one of them with respect to the other. Theoretical and experimental analyses have found that the electronic properties of TBG depend very strongly on the angle between the layers. In fact, a handful of “magic” angles have been predicted at which TBG becomes a supercondutor, and this has even been verified experimentally.

The model commonly used to study TBG is an effective one, and was derived by
Bistritzer and MacDonald. In this talk, I will present recent results on developing a framework to study TBG from first principles. To be more exact, we consider a tight-binding model for the electrons, but make no further approximations. Using a renormalization group technique, we construct a perturbative expansion to study TBG that is convergent when the twisting angle satisfies certain diophantine conditions.

This is joint work with V. Mastropietro.

28-29-30/04/2025 & 5-6/05/2025 : Douglas Lundholm @PoliMi

quantumseminarSeminar PoliMi 
Schedule:   Monday, April 28th, 14.00 - 16.00
            Tuesday, April 29th, 10:00 - 12:00
            Wednesday, April 30, 14:00 - 16:00
            Monday, May 5th, 14:00 - 16:00
            Wednesday, May 7th, 14:00 - 16:00


Aula Seminari (3rd floor)
Bd. 14 "Nave", Via Bonardi 9,
D-Mat Mathematics Department of PoliMi, Politecnico di Milano.

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SPEAKER: Douglas Lundholm (Uppsala Universitet)

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Mathematics of the 2D anyon gas

In the theory of quantum statistics, if one follows mathematical logic to its conclusion, one reaches the possibility of intermediate exchange statistics and “anyons”, i.e. identical particles different from bosons and fermions. Over the course of about 50 years this topic has evolved from merely an exotic possibility to an almost inevitability when orientation symmetry is broken, such as in effectively two-dimensional systems subject to rotation or an external magnetic field. The signature example is the fractional quantum Hall effect, and in just the last few years very strong signatures of individual anyons have finally arrived from experiments. However, the many-body theory necessary to study precise collective properties of anyons has remained rather undeveloped until relatively recently. This mini course will focus on the mathematics of the many-anyon gas, introduce some of the main concepts involved, and thus provide a foundation for further exploration of the topic, starting from the toy model of ideal anyons, to more realistic emergent models, and also promising applications to quantum computing.

Lecture plan:

I. Quantum statistics & transmutation

II. Local exclusion & stability

III. The almost-bosonic interacting anyon gas

IV. Emergent models: FQHE & polarons

V. Non-abelian anyons & topological quantum computing

Further information: https://sites.google.com/view/qmp25-intensiveperiod/courses

11/04/2025 : Annalisa Panati @UniMi

quantumseminarSeminar UniMi 
Friday, April 11, 2025

Aula 6,
Dipartimento di Matematica,
Università degli Studi di Milano,
Via Cesare Saldini 50.

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SPEAKER: Annalisa Panati (Université de Toulon, Centre de Physique Théorique)

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Entropic fluctuations in quantum two-time measurement framework

Non-equilibrium statistical mechanics has seen some impressive developments in the last three decades, since the ground-breaking formulation of the transient and steady entropic Fluctuation Relations (FR) in the early nineties.
The extension of these results to the quantum setting has turned out to be surprisingly challenging and it is still an ongoing effort. Kurchan and Hal Tasaki’s seminal works (2000) showed quantum formulation of the transient version of FR is possible by introducing the two-time measurement framework.
In this talk, we present some results in a recent series of papers, where we attempt to introduce a quantum equivalent of steady entropic functional and compare it to the transient version for open quantum system. We consider both the case of idealised direct measurement on the reservoirs and experimentally accessible indirect measurement through coupling with an ancilla. We analyse in particular stability with respect to the initial state. In order to deal with the thermodynamic limit and to have general results, we use methods of $C^*$- algebras and modular theory.


(Joint work with T. Benoist, L. Bruneau, V. Jakšić, C.A. Pillet)

03/04/2025 : Antoine Borie @UniMi

quantumseminarSeminar UniMi 
Thursday, April 3, 2025 - 11:00

Aula dottorato,
Dipartimento di Matematica,
Università degli Studi di Milano,
Via Cesare Saldini 50.

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SPEAKER: Antoine Borie (Université de Rennes)

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Scattering for the positive density Hartree equation

In this talk, we explore the long-time behavior of solutions to of the positive density Hartree equation, which models the evolution of a homogeneous quantum gas. Our focus is the stability of certain stationary states, extending the original result introduced by Mathieu Lewin and Julien Sabin to higher dimensions and more singular interaction potentials. Using tools from dispersive partial differential equations, such as Strichartz estimates and fractional Leibniz rules, we develop a new approach tailored to density matrices.

This talk is based on joint work with Julien Sabin (Rennes University ) and Sonae Hadama (Kyoto University).

17/12/2024 : Jonas Lampart @PoliMi

quantumseminarSeminar PoliMi 
Tuesday, December 17, 2024 - 11:30

Aula Seminari MOX (6th floor), D-Mat
Mathematics Department of PoliMi
Campus Leonardo, bd.14 "Nave".

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SPEAKER: Jonas Lampart (CNRS & Université de Bourgogne)

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Superfluidity and the spectrum of polaron Hamiltonians

I will discuss how superfluidity manifests itself in the spectrum of the Hamiltonian for a test particle travelling through a Bose Einstein condensate.

In the Bogoliubov-Fröhlich polaron model, a stable polaron with momentum P corresponds to a ground state of the Hamiltonian at fixed total momentum. I will explain a recent result in collaboration with Benjamin Hinrichs, which shows that a ground state exists if the momentum is less than mc, where m is the particle mass and c is the slope at zero momentum of the dispersion relation of the Bogoliubov phonons.