Publications associées à Rectangular waveguides for applications using terahertz signals

SPEEDING UP KRYLOV SUBSPACE METHODS FOR COMPUTING f(A)b VIA RANDOMIZATION

This work is concerned with the computation of the action of a matrix function f(A), such as the matrix exponential or the matrix square root, on a vector b. For a general matrix A, this can be done by computing the compression of A onto a suitable Krylov ...

Siam Publications2024

Accelerator-driven Data Arrangement to Minimize Transformers Run-time on Multi-core Architectures

David Atienza Alonso, Giovanni Ansaloni, Alireza Amirshahi

The increasing complexity of transformer models in artificial intelligence expands their computational costs, memory usage, and energy consumption. Hardware acceleration tackles the ensuing challenges by designing processors and accelerators tailored for t ...

2024

Randomized low-rank approximation and its applications

Ulf David Persson

In this thesis we will present and analyze randomized algorithms for numerical linear algebra problems. An important theme in this thesis is randomized low-rank approximation. In particular, we will study randomized low-rank approximation of matrix functio ...

EPFL2024

The Power of Two Matrices in Spectral Algorithms for Community Recovery

Colin Peter Sandon

Spectral algorithms are some of the main tools in optimization and inference problems on graphs. Typically, the graph is encoded as a matrix and eigenvectors and eigenvalues of the matrix are then used to solve the given graph problem. Spectral algorithms ...

Ieee-Inst Electrical Electronics Engineers Inc2024

Hybrid silicon photonics for terahertz applications

Ileana-Cristina Benea-Chelmus

This talk will highlight opportunities for terahertz science and technology from nonlinear integrated photonic circuits by exploring waveguides, resonators and terahertz antennas. Their present and future applications in metrology, emission and waveform co ...

Spie-Int Soc Optical Engineering2024

Spectral Estimators for High-Dimensional Matrix Inference

Farzad Pourkamali

A key challenge across many disciplines is to extract meaningful information from data which is often obscured by noise. These datasets are typically represented as large matrices. Given the current trend of ever-increasing data volumes, with datasets grow ...

EPFL2024

Time-Domain Integration of Broadband Terahertz Pulses via Tapered Two-Wire Waveguide

Alessandro Tomasino

In this work, we report on the implementation of a time-domain integrator device operating on arbitrary broadband Terahertz (THz) pulses. This analog signal-processing functionality is implemented by employing a two-wire waveguide (TWWG) variant, based on ...

IEEE2023

Ultra-broadband terahertz radiation by supercontinuum generation and optical rectification in a dispersion-engineered waveguide: a numerical study

Ileana-Cristina Benea-Chelmus, Aleksei Gaier

In this work, we propose a numerical approach based on forward coupled mode modeling to simultaneously evaluate second- and third-order nonlinearities inside a dispersion-engineered waveguide towards the goal of generating broadband terahertz (THz) radiati ...

IEEE2023

500 GHz field-resolved detection in thin-film lithium niobate devices

Ileana-Cristina Benea-Chelmus, Alessandro Tomasino

In this work, we show the coherent reconstruction of terahertz (THz) transients in thin-film lithium niobate integrated photonics circuits. Our devices modulate the intensity of a probe beam guided through a Mach-Zehnder interferometer (MZI) structure, und ...

IEEE2023

Broadband spectroscopy and inelastic light scattering on the canted antiferromagnet hematite for antiferromagnetic magnonics

Mohammad Hamdi

Collective spin excitations propagating in magnetically ordered materials are called spin waves (SWs) or magnons. They are promising for low-power and beyond-CMOS information processing, which do not suffer from the ohmic losses. SWs in ferromagnets (antif ...

EPFL2023

Towards a nonperturbative construction of the S-matrix

Francesco Riva, Matthew Thomas Walters, Brian Quinn Henning

We present a nonperturbative recipe for directly computing the S-matrix in strongly-coupled QFTs. The method makes use of spectral data obtained in a Hamiltonian framework and can be applied to a wide range of theories, including potentially QCD. We demons ...

Springer Nature2023

A model for the consolidation of hybrid textiles considering air entrapment, dissolution and diffusion

Véronique Michaud, Vincent Werlen, Christian Rytka

A new model is proposed for the consolidation of hybrid textiles, in which air entrapment and dissolution are considered. One of the key parameters is tow permeability, which is described by the analytical model of Gebart and validated at very high fibre v ...

ELSEVIER SCI LTD2023

Ultrafast Electron Microscopy of Nanoscale Charge Dynamics in Semiconductors

Fabrizio Carbone, Ivan Madan, Giovanni Maria Vanacore, Francesco Barantani, Ido Kaminer, Kangpeng Wang, Simone Gargiulo

The ultrafast dynamics of charge carriers in solids plays a pivotal role in emerging optoelectronics, photonics, energy harvesting, and quantum technology applications. However, the investigation and direct visualization of such nonequilibrium phenomena re ...

AMER CHEMICAL SOC2023

Post-Moore's Law Fusion: High-Bandwidth Memory, Accelerators, and Native Half-Precision Processing for CPU-Local Analytics

Anastasia Ailamaki, Viktor Sanca

Modern data management systems aim to provide both cutting-edge functionality and hardware efficiency. With the advent of AI-driven data processing and the post-Moore Law era, traditional memory-bound scale-up data management operations face scalability ch ...

2023

T-5 configurations and hyperbolic systems

Carl Johan Peter Johansson, Riccardo Tione

In this paper, we study the rank-one convex hull of a differential inclusion associated to entropy solutions of a hyperbolic system of conservation laws. This was introduced in [B. Kirchheim, S. Muller and V. S(sic)ver & aacute;k, Studying Nonlinear PDE by ...

WORLD SCIENTIFIC PUBL CO PTE LTD2023

Learned Compressive Representations for Single-Photon 3D Imaging

Claudio Bruschini, Edoardo Charbon, Andrei Ardelean, Mohit Gupta

Single-photon 3D cameras can record the time-of-arrival of billions of photons per second with picosecond accuracy. One common approach to summarize the photon data stream is to build a per-pixel timestamp histogram, resulting in a 3D histogram tensor that ...

Ieee Computer Soc2023

Preconditioning techniques for generalized Sylvester matrix equations

Yannis Dirk Voet

Sylvester matrix equations are ubiquitous in scientific computing. However, few solution techniques exist for their generalized multiterm version, as they now arise in an increasingly large number of applications. In this work, we consider algebraic parame ...

2023

On the fast assemblage of finite element matrices with application to nonlinear heat transfer problems

Yannis Dirk Voet

The finite element method is a well-established method for the numerical solution of partial differential equations (PDEs), both linear and nonlinear. However, the repeated re -assemblage of finite element matrices for nonlinear PDEs is frequently pointed ...

ELSEVIER SCIENCE INC2023

A 16-bit Floating-Point Near-SRAM Architecture for Low-power Sparse Matrix-Vector Multiplication

David Atienza Alonso, Giovanni Ansaloni, Marco Antonio Rios, Grégoire Axel Eggermann

State-of-the-art Artificial Intelligence (AI) algorithms, such as graph neural networks and recommendation systems, require floating-point computation of very large matrix multiplications over sparse data. Their execution in resource-constrained scenarios, ...

New York2023

Hilbert series, the Higgs mechanism, and HEFT

Brian Quinn Henning

We expand Hilbert series technologies in effective field theory for the inclusion of massive particles, enabling, among other things, the enumeration of operator bases for non-linearly realized gauge theories. We find that the Higgs mechanism is manifest a ...

Springer Nature2023