Stephan Roche

Institut Català de Nanociència i Nanotecnologia (ICN2)

Engineering Sciences

Stephan Roche is ICREA Research Prof. working at the Catalan Institute of Nanosciences and Nanotechnology-ICN2 and the Barcelona Institute of Science and Technology. He leads the "Theoretical and Computational Nanoscience" group which focuses on quantum transport in Dirac materials (graphene and topological insulators). He pioneered the development of linear scaling computational approaches for wavepacket dynamics, Kubo conductivities, and Landauer-Büttiker conductance in disordered materials.

He studied Theoretical Physics at ENS and UJF (France), received a PhD in Physics in 1996 (CNRS), and worked in Japan, Spain and Germany. He was appointed Prof. assistant at UJF (2000) and CEA Researcher (2004), and received the Friedrich Wilhelm Bessel prize from the A.v. Humboldt Foundation (Germany). He is the PI of ICN2 in the GRAPHENE FLAGSHIP, and deputy leader of the Graphene Spintronics WP.

Research interests

At ICN2, S. Roche and his group theoretically explore exotic quantum transport in Dirac Matter including graphene and topological insulators. Main current  interests include (i) the study of quantum interferences and decoherence mechanisms in presence of electron-phonon coupling and spin-orbit interaction, (ii) spin dynamics and spin-torques phenomena in heterostructures, (iii) spin Hall and quantum spin Hall effects, valley Hall effects in graphene and (iv) thermoelectricity in two-dimensional materials.

Selected publications

– Van Tuan D, Marmolejo-Tejada JM, Waintal, X Nikolić BK, Valenzuela SO & Roche S 2016, ‘Spin Hall Effect and Origins of Nonlocal Resistance in Adatom-Decorated Graphene’, Physical Review Letters, vol. 117, p. 176602

– Tuan DV & Roche S 2016, ‘Spin Manipulation in Graphene by Chemically Induced Pseudospin Polarization’, Physical Review Letters, 116, 10, 106601.

– Cummings AW & Roche S 2016, ‘Effects of Dephasing on Spin Lifetime in Ballistic Spin-Orbit Materials’, Physical Review Letters 116, 086602.

– Settnes M, Leconte L, Barrios-Vargas JE, Jauho AP & Roche S 2016, ‘Quantum transport in graphene in presence of strain-induced pseudo-Landau leves’, 2D Materials 3, 034005.

– Sledzinska M, Graczykowski B, Placidi M, Saleta Reig D, Sachat AEI, Reparaz JS, Alzina F, Mortazavi B, Quey R, Colombo L, Roche S & Sotomayor Torres CM 2016, ´Thermal conductivity of MoS2 polycrystalline nanomembranes’, 2D Materials 3, 035016.

– Van Tuan D, Ortmann F, Cummings AW, Soriano D & Roche S 2016, ‘Spin dynamics and relaxation in graphene dictated by electron-hole puddles’, Scientific Reports, 6, 21046.

– Woessner A, Alonso-González P, Lundeberg MB, Gao Y, Barrios-Vargas JE, Navickaite G, Ma Q,  Janner D, Watanabe K, Cummings AW, Taniguchi T, Pruneri V, Roche S, Jarillo-Herrero P, Hone J, Hillenbrand R & Koppens F 2016, ´Near-field photocurrent nanoscopy on bare and encapsulated graphene´, Nature Communications 7, 10783.

– Katagiri Y, Nakamura T, Ishii A, Ohata C, Hasegawa M, Katsumoto S, Cusati T, Fortunelli A, Iannaccone G, Fiori G, Roche S & Haruyama  J 2016, ‘Gate-tunable atomically-thin lateral MoS2 Schottky junction patterned by electron beam’ Nano Letters 16 (6), 37788-3794.

– Cresti A, Nikolíc BK, García JH & Roche S 2016, ‘Charge, spin and valley Hall effects in disordered graphene’, Rivista del Nuovo Cimento 39 (12): 587- 667.

Selected research activities

-Member of the organization Committee of Graphene 2016 (Genoa, Italy)