Events at Physics
Events on Thursday, January 25th, 2018
- R. G. Herb Condensed Matter Seminar
- Connecting the dots: the interactions and environment of electrons in zero dimensions
- Time: 10:00 am
- Place: 5310 Chamberlin
- Speaker: Xanthe Croot, University of Sydney
- Abstract: Quantum information can be encoded in the spin and charge states of electrons in semiconductor quantum dots. While qubits in these zero-dimensional systems have exhibited long coherence times and excellent one and two-qubit operability, there remain challenges - namely, unwanted environmental coupling and issues of scalability. In this talk, I will discuss interactions between microwave-driven electrons in GaAs quantum dots and their phonon environment, which can lead to qubit population inversions and decoherence. Techniques for probing the charge environment of the qubit will also be explored, and I will briefly touch on scalable readout protocols. Finally, I will outline progress in an architecture designed to facilitate controllable coupling between separated qubits, an important outstanding challenge for the field.
- Host: Eriksson
- Astronomy Colloquium
- "Probing Galaxy Cluster Formation Through Dynamics of the Hot, Intracluster Medium (ICM)"
- Time: 3:00 pm
- Place: 4421 Sterling Hall, Coffee and cookies 3:30 pm, Talk begins 3:45PM
- Speaker: Tom Jones, University of Minnesota, School of Physics and Astronomy
- Abstract: Galaxy clusters, made mostly of dark matter, are the most massive and last structures to form out of cosmic expansion. They grow on timescales of Gyr through accretion and mergers. They are also frequently harassed by adjacent, smaller clumps of dark matter. As a result of this complex evolution cluster dynamical states are also complex.The hot ICM plasma is the dominant baryonic cluster component. Because the ICM is weakly collisional it effectively captures important details of the formation dynamics and its history. While some events and processes are revealed conveniently through thermal X-ray emissions, other vital dynamical behaviors are highlighted primarily via non-thermal emissions, either within the ICM itself or through interactions between the ICM and relativistic plasmas deposited within by active galaxies. This non-thermal window into cluster formation dynamics is especially important in cluster outskirts, where thermal X-ray signals are weak. In this talk I will review these issues and some of our ongoing efforts to model and decipher distinctive non-thermal signals of ICM dynamics.
- Host: Astronomy Dept