72 citations · 706 across the 26 of their papers we have counts for
26 papers
Electronic and phonon contributions to the Thermoelectric properties of newly discovered half-Heusler alloys XHfPb (X= Ni, Pd, and Pt)
Paul O. Adebambo, Gboyega A. Adebayo, Roberto Guerra +1
In this work we calculate the thermoelectric figure of merit of XHfPb (X= Ni, Pd, and Pt) by computing the both the power factor and the lattice thermal conductivity by first princ…
Multiwalled nanotube faceting unravelled
Itai Leven, Roberto Guerra, Andrea Vanossi +2
Nanotubes show great promise for miniaturizing advanced technologies. Their exceptional physical properties are intimately related to their morphological and crystal structure. Cir…
The Smallest Archimedean Screw: Facet Dynamics and Friction in Multi-Walled Nanotubes
Roberto Guerra, Itai Leven, Andrea Vanossi +2
We identify a new material phenomenon, where minute mechanical manipulations induce pronounced global structural reconfigurations in faceted multi-walled nanotubes. This behavior h…
Thermal Friction Enhancement in Zwitterionic Monolayers
Melisa M. Gianetti, Roberto Guerra, Andrea Vanossi +2
We introduce a model for zwitterionic monolayers and investigate its tribological response to changes in applied load, sliding velocity, and temperature by means of molecular-dynam…
Registry dependent potential for interfaces of gold with graphitic systems
Wengen Ouyang, Oded Hod, Roberto Guerra
We present a semi-anisotropic interfacial potential (SAIP) designed to classically describe the interaction between gold and two-dimensional (2D) carbon allotropes such as graphene…
Friction of Physisorbed Nanotubes: Rolling or Sliding?
Davide Mandelli, Roberto Guerra
The structure and motion of carbon and h-BN nanotubes (NTs) deposited on graphene is inquired theoretically by simulations based on state-of-the-art interatomic force fields. Resul…
Static friction boost in edge-driven incommensurate contacts
Davide Mandelli, Roberto Guerra, Wengen Ouyang +2
We present a numerical investigation of the size scaling of static friction in incommensurate two dimensional contacts performed for different lateral loading configurations. Resul…
Experimental observation of the Aubry transition in two-dimensional colloidal monolayers
T. Brazda, A. Silva, N. Manini +4
The possibility to achieve entirely frictionless, i.e. superlubric, sliding between solids, holds enormous potential for the operation of mechanical devices. At small length scales…
Ballistic thermophoresis of adsorbates on free-standing graphene
Emanuele Panizon, Roberto Guerra, Erio Tosatti
The textbook thermophoretic force which acts on a body in a fluid is proportional to the local temperature gradient. The same is expected to hold for the macroscopic drift behavior…
Graphene nanoribbons on gold: Understanding superlubricity and edge effects
Lorenzo Gigli, Nicola Manini, Andrea Benassi +3
We address the atomistic nature of the longitudinal static friction against sliding of graphene nanoribbons (GNRs) deposited on gold, a system whose structural and mechanical prope…
Graphene on h-BN: to align or not to align?
Roberto Guerra, Merel van Wijk, Andrea Vanossi +2
The contact strength, adhesion and friction, between graphene and an incommensurate crystalline substrate such as {\it h}-BN depends on their relative alignment angle . The well…
Slider Thickness Promotes Lubricity: from 2D Islands to 3D Clusters
Roberto Guerra, Erio Tosatti, Andrea Vanossi
The sliding of three-dimensional clusters and two-dimensional islands adsorbed on crystal surfaces represent an important test case to understand friction. Even for the same materi…
Friction and Adhesion mediated by supramolecular host-guest complexes
Roberto Guerra, Andrea Benassi, Andrea Vanossi +2
The adhesive and frictional response of an AFM tip connected to a substrate through supramolecular host-guest complexes is investigated by dynamic Monte Carlo simulations. The vari…
Energetics and carrier transport in doped Si/SiO2 quantum dots
Nuria Garcia-Castello, Sergio Illera, Joan Daniel Prades +3
In the present theoretical work we have considered impurities, either boron or phosphorous, located at different substitutional sites in silicon quantum dots (Si-QDs) with diameter…
Preferential positioning of dopants and co-dopants in embedded and freestanding Si nanocrystals
Roberto Guerra, Stefano Ossicini
In this work we aim at understanding the effect of n-type and p-type substitutional doping in the case of matrix-embedded and freestanding Si nanocrystals. By means of ab-initio ca…
Frictional Transition from Superlubric Islands to Pinned Monolayers
Matteo Pierno, Lorenzo Bruschi, Giampaolo Mistura +6
The inertial sliding of physisorbed submonolayer islands on crystal surfaces contains unexpected information on the exceptionally incommensurate smooth sliding state associated wit…
Static friction scaling of physisorbed islands: the key is in the edge
Nicola Varini, Andrea Vanossi, Roberto Guerra +3
The static friction preventing the free sliding of nanosized rare gas solid islands physisorbed on incommensurate crystalline surfaces is not completely understood. Simulations mod…
Role of strain in interacting silicon nanoclusters
Roberto Guerra, Stefano Ossicini
The possibility of controlling the optical transition probability between neighbouring silicon nanoclusters (Si-NCs) constitutes nowadays an attractive prospect in nanophotonics an…
Optical absorption and emission of silicon nanocrystals: From single to collective response
Roberto Guerra, Francesco Cigarini, Stefano Ossicini
We report on the possibility of describing the absorption and emission characteristics of an ensemble of silicon nanocrystals (NCs) with realistic distributions in the NC size, by…
The Influence of Silicon Nanoclusters on the Optical Properties of a-SiNx Samples: A Theoretical Study
R. Guerra, M. Ippolito, S. Meloni +1
By means of ab-initio calculations we investigate the optical properties of pure a-SiN samples, with , and samples embedding silicon nanoclusters (NCs) of dia…
Local-field effects in silicon nanoclusters
Roberto Guerra, Margherita Marsili, Olivia Pulci +1
The effect of the local fields on the absorption spectra of silicon nanoclusters (NCs), freestanding or embedded in SiO2, is investigated in the DFT-RPA framework for different siz…
Silicon Nanocrystallites in SiO2 Matrix: The Role of Disorder and Size
Roberto Guerra, Ivan Marri, Rita Magri +4
We compare, through first-principles pseudopotential calculations, the structural, electronic and optical properties of different size silicon nanoclusters embedded in a SiO2 cryst…
Local-fields and disorder effects in free-standing and embedded Si nanocrystallites
Roberto Guerra, Elena Degoli, Margherita Marsili +2
The case study of a 32-atoms Si nanocrystallite (NC) embedded in a SiO2 matrix, both crystalline and amorphous, or free-standing with different conditions of passivation and strain…
Ballistic nanofriction
Roberto Guerra, Ugo Tartaglino, Andrea Vanossi +1
Sliding parts in nanosystems such as Nano ElectroMechanical Systems (NEMS) and nanomotors, increasingly involve large speeds, and rotations as well as translations of the moving su…