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ResearchI am a theoretical condensed matter physicist primarily interested in nanoscale systems. On such small length scales, the physics is drastically different from what we know in our allday life and is dominated by the laws of quantum mechanics. I investigate different ways of taking advantage of quantum mechanics to design for example electronic components with desirable properties. Specific research topics include:Superconducting proximity effect and Majorana fermions. When a superconductor is tunnel coupled to for example a semiconductor, tunneling of Cooper pairs leads to proximityinduced superconductivity in the semiconductor. I am interested in how this can be used to engineer superconductors with new exciting properties, such as topological superconductors hosting socalled Majorana fermion excitations. I am also studying how Majoranas can best be used for quantum information processing. In addition, I investigate how superconductors can be used to mediate a longdistance coupling between other quantum systems, for example spin qubits defined in nanowires.
Quantum transport in nanostructures. Using primarily quantum master equation approaches, I study nonequilibrium transport in strongly interacting nanostructures, such as quantum dots, nanowires, and singlemolecule devices. One goal is to understand how quantum transport can be used to extract spectroscopic information about a nanoscale system. Another goal is to propose devices where a combination of interaction and quantum mechanical effects give rise to some desired functionality, such as spinpolarized currents, negative differential resistance, or rectification.
Heat transport and thermoelectric devices. The thermoelectric effect allows direct conversion of a heat gradient into an electric current or voltage. I investigate the prospect of using the unique electronic properties of nanoscale devices to make highly efficient thermoelectric energy converters. Thermoelectic efficiency is reduced by losses from heat currents carried by phonons. Therefore, I investigate also phonon transport in nanosctructures, with the goal of designing devices where phonon transport is blocked without destroying the electronic transport properties.


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TeachingI currently teach the undergraduate course Elektroniska material (Electronic materials) and a PhD level course on Theory of superconductivity. 
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