Ultrafast Condensed Matter Physics
The aim of our research is to investigate fundamental phenomena occurring in matter at ultrashort timescale. For this reason we develop innovative ultrafast systems with the ultimate goal to access how light interacts with matter to unveil the origin of the properties of materials that are of high technological interest.
Ultrashort pulse generation
one of the main activities is the generation of ultrashort optical pulses in a broad spectrum of frequencies via concepts of nonlinear optics. In particular, we develop optical parametric amplifiers that are able to exploit extremely broadband phase matching conditions in order to amplify weak supercontinua; in this way we generated pulses approaching a single optical cycle from the UV to the mid-IR and even THz frequency range. This activity is fundamental for all the studies performed in condensed matter and in nanosystems.
Ultrafast phenomena in condensed matter
This research activity consists in the use of ultrashort pulses for optical studies of light matter interaction with the possibility to access events occurring on an elementary time scale with unprecedented sensitivity. The tunability of the pulses plays a key role in ultrafast spectroscopy. For this reason, our main activity is the use of ultrashort pulses for the study of elementary processes occurring in matter upon impulsive photoexcitation with unmatched combination of temporal resolution and spectral coverage. One example of studies on solid state systems deal with the non-equilibrium properties of electrons in semiconductors and their thermalization dynamics that are related to the fundamental interaction mechanisms between charges and lattice.
Nanophotonics and plasmonics
One additional activity is the study of ultrafast phenomena and plasmonic effects in gold nanoantennas with main focus on the photoluminescence and nonlinear properties of these structures. Recently we also started a new activity on mid-infrared plasmonics in heavily doped semiconductors. In this framework, we are developing a new generation of active plasmonic devices that are fully CMOS compatible with foreseeable applications in fundamental science and in sensing.
Ultrafast quantum nanotransport
Recently we demonstrated carrier-envelope optical phase control of the current in a nano-optoelectronic device with structural dimensions down to 8 nm. The results are enabled by tailoring the electric field of single-cycle light pulses that drive tunneling processes with a bandwidth in the PHz range. The experiments allow full control over current amplitude and direction operating on sub-cycle optical time scales.
One important aspect of combining optical phase control with three-dimensional nanoscopic confinement is represented by the fact that extremely weak optical pulses in the pico-Joule range can manipulate currents on the order of a single electron per half cycle. This finding opens up the exciting perspective of studying charge transport at sub-cycle optical time scales in strongly confined nanosystems where quantum effects are expected to play a dominant role. For example, phenomena like Coulomb blockade or resonant tunneling may be studied in an unprecedented frequency range and even at room temperature.
