Valentina Brosco

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One of the challenges of adiabatic control theory is the proper inclusion of the effects of dissipation. Here we study the adiabatic dynamics of an open two-level quantum system deriving a generalized master equation to consistently account for the combined action of the driving and dissipation. We demonstrate that in the zero-temperature limit the ground(More)
Valentina Brosco,1,2,3 Markus Jerger,4 Pablo San-José,3 Gergely Zarand,5,6 Alexander Shnirman,7,6 and Gerd Schön3,6 1Dipartimento di Fisica, Università “La Sapienza,” P.le A. Moro 2, 00185 Roma, Italy 2ISC-CNR, Via dei Taurini 19, 00185 Roma, Italy 3Institut für Theoretische Festkörperphysik, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany(More)
Cooper pair pumping is a coherent process. We derive a general expression for the adiabatic pumped charge in superconducting nanocircuits in the presence of level degeneracy and relate it to non-Abelian holonomies of Wilczek and Zee. We discuss an experimental system where the non-Abelian structure of the adiabatic evolution manifests in the pumped charge.
Motivated by recent experiments, which demonstrated lasing and cooling of the electromagnetic modes in a resonator coupled to a superconducting qubit, we describe the specific mechanisms creating the population inversion, and we study the spectral properties of these systems in the lasing state. Different levels of the theoretical description, i.e., the(More)
We discuss the transport properties of a disordered two-dimensional electron gas with strong Rashba spin-orbit coupling. We show that in the high-density regime where the Fermi energy overcomes the energy associated with spin-orbit coupling, dc transport is accurately described by a standard Drude's law, due to a nontrivial compensation between the(More)
To fix the notation, let us start by giving some details on the helicity eigenstates basis. The helicity operator is defined as S = [p̂⇥ ~ ]z and its eigenstates, |ksi, with s = ±1, satisfy the relation S|k±i = ±|k±i. A simple calculation shows in particular that |k±i can be expressed in terms of the standard spin eigenstates, |k "i and |k #i, as |k±i =(More)
In Kohn-Sham density functional theory (DFT) the interacting electron problem is mapped into a noninteracting problem in an effective potential v(KS). It is known that the charge gap of the interacting system is different from the gap of the effective problem due to a jump Δxc in v(KS) when an electron is added but its magnitude and its role in the(More)
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