Publications de Fei Guo | EPFL Graph Search

Duality and degeneracy lifting in two-dimensional electron liquids on SrTiO3(001)

Two-dimensional electron liquids (2DELs) have increasing technological relevance for ultrafast electronics and spintronics, yet significant gaps in their fundamental understanding are exemplified on the prototypical SrTiO3. We correlate the exact SrTiO3(00 ...

Springer Science and Business Media LLC2025

Magneto-optical response of the magnetic semiconductors EuCd2X2 (X =P, As, Sb)

Jan Hugo Dil, Ivica Zivkovic, Michele Puppin, Fei Guo

In this study, we identify EuCd2X2 (for X = P, As, Sb) as a series of magnetic semiconductors. We examine how the band gap of the series responds to X changing from phosphorus (P), to arsenic (As), and finally antimony (Sb). We characterize the samples usi ...

2024

Real-and reciprocal space characterization of the three-dimensional charge density wave in quasi-one-dimensional CuTe

Arnaud Magrez, Jan Hugo Dil, Michele Puppin, Fei Guo

Low-dimensional materials are susceptible to electronic instabilities such as charge density waves (CDWs), originating from a divergence in the Lindhard electron response function, combined with a finite electron-phonon coupling strength. In this paper, we ...

American Physical Society (APS)2024

High-resolution MHz time- and angle-resolved photoemission spectroscopy based on a tunable vacuum ultraviolet source

Henrik Moodysson Rønnow, Marco Grioni, Fabrizio Carbone, Jan Hugo Dil, Thomas La Grange, Michele Puppin, Fei Guo

The time- and angle-resolved photoemission spectroscopy (trARPES) allows for direct mapping of the electronic band structure and its dynamic response on femtosecond timescales. Here, we present a new ARPES system, powered by a new fiber-based femtosecond l ...

Aip Publishing2024

Device Performance of Emerging Photovoltaic Materials (Version 4)

Mohammad Khaja Nazeeruddin, Fei Guo, Tor Jesper Jacobsson

Following the 3rd release of the "Emerging PV reports", the best achievements in the performance of emerging photovoltaic (e-PV) devices in diverse e-PV research subjects are summarized, as reported in peer-reviewed articles in academic journals since Augu ...

Wiley-V C H Verlag Gmbh2023

EuCd2As2: A Magnetic Semiconductor

Jan Hugo Dil, Ivica Zivkovic, Michele Puppin, Jian Rui Soh, Fei Guo

EuCd2As2 is now widely accepted as a topological semimetal in which a Weyl phase is induced by an external magnetic field. We challenge this view through firm experimental evidence using a combination of electronic transport, optical spectroscopy, and exci ...

2023

Spontaneously Self-Assembly of a 2D/3D Heterostructure Enhances the Efficiency and Stability in Printed Perovskite Solar Cells

Mohammad Khaja Nazeeruddin, Tom Theodorus Antonius Lummen, Fei Guo, Xuehui Liu, Chaohui Li, Chuan Wang

As perovskite solar cells (PSCs) are highly efficient, demonstration of high-performance printed devices becomes important. 2D/3D heterostructures have recently emerged as an attractive way to relieving the film inhomogeneity and instability in perovskite ...

2020

Vertically Aligned 2D/3D Pb-Sn Perovskites with Enhanced Charge Extraction and Suppressed Phase Segregation for Efficient Printable Solar Cells

Mohammad Khaja Nazeeruddin, Tom Theodorus Antonius Lummen, Fei Guo, Xuehui Liu, Chaohui Li, Shi Chen

The concept of mixed 2D/3D heterostructures has emerged as an effective method for improving the stability of lead halide perovskite solar cells, which has been, however, rarely reported in lead-tin (Pb-Sn) mixed perovskite devices. Here, we report a scala ...

2020

Device Performance of Emerging Photovoltaic Materials (Version 1)

Mohammad Khaja Nazeeruddin, Fei Guo, Henry Snaith, Tor Jesper Jacobsson

Emerging photovoltaics (PVs) focus on a variety of applications complementing large scale electricity generation. Organic, dye-sensitized, and some perovskite solar cells are considered in building integration, greenhouses, wearable, and indoor application ...

WILEY-V C H VERLAG GMBH2020