Publications associées à Fluorescence and phosphorescence from individual C-60 molecules excited by local electron tunneling

Quantum-mechanical effects in photoluminescence from thin crystalline gold films

Giulia Tagliabue, Fateme Kiani Shahvandi, Theodoros Tsoulos, Alan Richard Bowman

Luminescence constitutes a unique source of insight into hot carrier processes in metals, including those in plasmonic nanostructures used for sensing and energy applications. However, being weak in nature, metal luminescence remains poorly understood, its ...

2024

Plasmonically enhanced molecular junctions for investigation of atomic-scale fluctuations in self-assembled monolayers

Sakthi Priya Amirtharaj

Molecular junctions represent a fascinating frontier in the realm of nanotechnology and are one of the smallest optoelectronic devices possible, consisting of individual molecules or a group of molecules that serve as the active element sandwiched between ...

EPFL2024

Tunnel junction sensing of TATP explosive at the single-molecule level

Radomir Zikic, Helena Miljkovic

Triacetone triperoxide (TATP) is a highly potent homemade explosive commonly used in terrorist attacks. Its detection poses a significant challenge due to its volatility, and the lack of portability of current sensing techniques. To address this issue, we ...

Royal Soc Chemistry2023

Charging and Electric Field Effects on Hydrogen Molecules Physisorbed on Graphene

Klaus Kern, Shai Mangel, Alessio Scavuzzo, Tobias Wollandt

Molecular hydrogen adsorbed on graphene was investigated by analyzing rotational excitation spectra obtained with a gate-tunable scanning tunneling microscope (STM). Through the shift of the rotational excitation energy, the tunability of physisorbed H2 on ...

AMER CHEMICAL SOC2023

Single molecule fluorescence and phosphorescence studies using a scanning tunneling microscope

Abhishek Grewal

This thesis investigates novel single-molecule luminescence phenomena at their inherent, sub-molecular length scale. The microscopic understanding of luminescence processes will be crucial for the continued improvement of organic optoelectronic and semicon ...

EPFL2022

Thiazole Boron Difluoride Dyes with Large Stokes Shift, Solid State Emission and Room-Temperature Phosphorescence

Jieping Zhu, Shuo Tong, Wei Wang

The small Stokes shift and weak emission in the solid state are two main shortcomings associated with the boron-dipyrromethene (BODIPY) family of dyes. This study presents the design, synthesis and luminescent properties of boron difluoro complexes of 2-ar ...

WILEY-V C H VERLAG GMBH2022

Electron Emission Regimes of Planar Nano Vacuum Emitters

Marco Turchetti, Alberto Nardi, Yujia Yang

Recent advancements in nanofabrication have enabled the creation of vacuum electronic devices with nanoscale free-space gaps. These nanoelectronic devices promise the benefits of cold-field emission and transport through free space, such as high nonlineari ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022

Tunneling processes through magnetic impurities on superconducting surfaces: Yu-Shiba-Rusinov states and the Josephson effect

Haonan Huang

Magnetic impurities generate a wealth of phenomena on surfaces. On metals, conducting electrons screen the magnetic moment giving rise to the Kondo effect. On superconductors, the Yu-Shiba-Rusinov (YSR) states emerge inside the superconducting gap due to t ...

EPFL2021

Vibrationally inelastic scattering of HCl from Ag(111)

Jan Daniel Geweke

Using molecular beam cooled samples and quantum state-selective detection, we observe v = 0 -> 1 vibrational transitions when HCl (v = 0) collides with an Ag(111) surface and derive both the incidence energy and surface temperature dependence of the transi ...

AMER INST PHYSICS2020

Dynamics of nanoscale systems probed by time-resolved STM-induced luminescence

Anna Maria Roslawska

The efficiency and peculiarities of processes such as surface adsorption or electron-to-photon energy conversion in organic and inorganic structures are determined by the dynamics at the scale of individual molecules, atoms and charges. The timescales of s ...

EPFL2019

Nanoscale Lithography and Thermometry with Thermal Scanning Probes

Samuel Tobias Howell, Samuel Zimmermann

Thermal scanning probe lithography (t-SPL) is an advanced lithography technique in which a heated atomic force microscope tip locally modifies a sample material. Due to the nanometer-sized tip apex diameter, t-SPL enables patterning of sub-10 nm structures ...

EPFL2018

Scanning Tunneling Spectroscopy with Superconducting Junctions : From Single Channel Transport to Local Pair Breaking Potentials

Jacob Senkpiel

This thesis contains two major topics, the restriction of tunneling to only a few channels in the scanning tunneling microscope (STM) and the interaction of local magnetic impurities with superconductivity. At a temperature of 15mK, the quantum back-action ...

EPFL2018

Bimodal exciton-plasmon light sources controlled by local charge carrier injection

Klaus Kern, Christoph Grosse, Anna Maria Roslawska

Electrical charges can generate photon emission in nanoscale quantum systems by two independent mechanisms. First, radiative recombination of pairs of oppositely charged carriers generates sharp excitonic lines. Second, coupling between currents and collec ...

AMER ASSOC ADVANCEMENT SCIENCE2018

Nonadiabatic effects in electronic and nuclear dynamics

Majed Chergui, Ursula Röthlisberger, Jiri Vanicek, Aurélien Kevin Fabrice Patoz, Tomas Zimmermann, Elisa Liberatore, Nicholas John Browning, Martin Peter Bircher

Due to their very nature, ultrafast phenomena are often accompanied by the occurrence of nonadiabatic effects. From a theoretical perspective, the treatment of nonadiabatic processes makes it necessary to go beyond the (quasi) static picture provided by th ...

2017

Multilaser Conformer-Selective Spectroscopy of Cold Biomolecular Ions in the Gas Phase

Aleksandr Pereverzev

Proteins and even small peptides play crucial role in almost any biological. Biological activity and functionality of these building blocks of life are determined not only by their primary structure, but also by their 3D orientation â secondary, tertiary ...

EPFL2017

Modeling and optimization of Tunnel-FET architectures exploiting carrier gas dimensionality

Cem Alper

The semiconductor industry, governed by the Moore's law, has achieved the almost unbelievable feat of exponentially increasing performance while lowering the costs for years. The main enabler for this achievement has been the scaling of the CMOS transistor ...

EPFL2017

Low p-type contact resistance by field-emission tunneling in highly Mg-doped GaN

Denis Martin, Nicolas Grandjean, Hironori Okumura

Mg-doped GaN with a net acceptor concentration (NA-ND) in the high 10 19 cm(-3) range was grown using ammonia molecular-beam epitaxy. Electrical properties of NiO contact on this heavily doped p-type GaN were investigated. A potential-barrier height of 0.2 ...

Amer Inst Physics2016

Nanometer-scale monitoring of quantum-confined Stark effect and emission efficiency droop in multiple GaN/AlN quantum disks in nanowires

Gwénolé Jean Jacopin

We report on a detailed study of the intensity dependent optical properties of individual GaN/AlN quantum disks (QDisks) embedded into GaN nanowires (NW). The structural and optical properties of the QDisks were probed by high spatial resolution cathodolum ...

Amer Physical Soc2016

Scanning Tunneling Microscopy using Superconducting Tips to Probe Absolute Spin Polarization

Matthias Alexander Eltschka

The interplay of superconductivity and magnetism is investigated for systems with dimensions ranging from the mesoscopic to the atomic scale by scanning tunneling microscopy (STM) at millikelvin temperatures and by numerical calculations. Based on geometri ...

EPFL2015

Monitoring Charge Carrier Dynamics at Atomic Length Scales by STM-induced Luminescence

Christoph Grosse

The goal of this thesis is the combination of the high spatial resolution of scanning tunneling microscopy (STM) with the high temporal resolution of optical spectroscopy, by monitoring the light emitted from the tunnel junction. Two complementary techniqu ...

EPFL2015