Colloidal semiconductor nanocrystals can be excellent light emitters or absorbers, and the optical properties like for example the light emission wavelength, direction and polarization can be controlled via the nanocrystal size, shape and composition. This makes them very interesting as active material in light emitting, lasing, or photovoltaic devices, and we are exploring novel approaches for proof of principle prototypes. On the other hand, metal nanostructures are very good conductors and can strongly interact with light in the visible and infrared spectral regions due to the presence of free electrons that can perform plasmon oscillations, which opened the field of nanoplasmonics. Recently, graphene has attracted great interest as a 2D material with very appealing conductive, plasmonic, and mechanical properties. We aim at combining the favorable properties of these materials in order to investigate complex optoelectronic systems and to pave the way for novel architectures for components in photodetectors, optical communication, photovoltaics, plasmonics, and nanoscale electronics. In collaboration with the Nanochemistry Department headed by Liberato Manna we develop novel lithography approaches for nanocrystal films that are based on the blocking of cation exchange reactions by a high energy beam exposure.
- Patterning nanocrystal films by masking cation exchange reactions (Nano Letters 2014)
- Microlasers fabricated by jet deposition of nanocrystal solutions (1: Nature Nanotechnology (DOI:10.1038/nnano.2014.213);2: Laser & Photonic Reviews 2012; 3:Nanoscale 2010))
- Three dimensional metal nanostructures for Surface-Enhanced-Raman Scattering (SERS). This activity is in collaboration with Dr. Andrea Toma and Dr. Remo Proietti Zaccaria from the IIT Nanophysics Department. (1:Advanced Materials 2014j; 2:Nanotechnology 2014; 3:ACS Nano 2014)
- Self assembly of nanomaterials in 3D structures using on superhydrophobic substrates. PPSC
- Functionalization of graphene with colloidal nanocrystals to develop novel photodetectors. J.Phys.ChemC
- Optical and electrical properties of nanocrystal films, consisting for example of CdTe tetrapods; CdSe/CdS nanorods; and octapods; CuSe nanocrystals; greigite nanoplatelets; spherical Au- spinel ferrite nanorods; and via scanning photocurrent microscopy.
We have micromanipulator probe stations in ambient (Karl Suss) and cryogenic (Janis Research) environment that can be coupled to various light sources and lasers spanning the spectral range from UV/VIS to NIR for photoelectrical characterization. Piezo-controlled mibots (Imina) reaching nanometer control can be used for probe contacts with optical and electron microscopes. The electrical instruments such as Keithley 2612 sourcemeters, lockin amplifiers, temperature controllers etc are controlled via a Labview platform. Our group has access to the nanochemistry and optical spectroscopy labs as well as to the clean room.
- Dr. Margherita Zavelani-Rossi, Politecnico di Milano
- Prof. Pingheng Tan, Chinese Academy of Sciences, Institute of Semiconductors
- Prof. Frank Koppens, ICFO, Spain
- Prof. Christian Riekel, ESRF Grenoble, France
- Prof. Eli Sutter, University of Nebraska, USA
- Prof. Davide Comoretto, University of Genoa
Roman Krahne was appointed Guest Professor at the Institute of Semiconductors, Chinese Academy of Sciences
- Roman Krahne Research gate profile
- Coffee-stain Laser video
- Physical Properties of Nanorods Book (Springer)
- Coordinator of the H2020-MSCA-RISE EU project COMPASS_691185 (2016-2020), total budget 1.2 M€
- H2020-MSCA-IF-2014 EU project 659144 - SCEL-TA (2015-2017), total budget 168k
- Fondazione CARIPLO 2013-2015, "Micro-lasers based on rod-shaped self-assembling colloidal semiconductor nanocrystals" with Politecnico di Milano, Dr. Margherita Zavelani-Rossi.
- PI for IIT in the FP7 FET Flagship "Graphene-Driven Revolutions in ICT and Beyond" (GRAPHENE), 2013-2016.
- Angelo Accardo has won the "Best Poster Award" in the
- Stefan Kudera has been awarded a Marie Sklodowska Curie Individual Fellowship
- The work on Masked Cation Exchange in Nanocrystal Films was included in the ELETTRA Highlights 2014
- The work on ENVIRONMENTAL INFLUENCE ON THE SECONDARY STRUCTURE OF AN AMYLOID BETA PEPTIDE was included in the ESRF highlights 2015.