Events at Physics
Events on Thursday, February 12th, 2015
- Astronomy Colloquium
- Dynamical Structure in the Galactic disk -- a new Decade of Galactic Discovery
- Time: 3:30 pm
- Place: 4421 Sterling Hall
- Speaker: Alice Quillen, Univeristy of Rochester, Astronomy & Astrophysics
- Abstract: Soon GAIA observations will increase our knowledge of the positions and velocities of millions of stars in the our Galaxy.
I will explore how star formation, spiral structure, perturbations and remnants from dwarf galaxies, and the Galactic bar cause substructure in local stellar velocity distributions.
I will discuss challenges in better measuring the shape and stellar distribution of the Milky Way, understanding dynamical processes in the disk and its formation and past evolution.
- Host: Prof Elena D'onghia
- R. G. Herb Condensed Matter Seminar
- Faculty Candidate Seminar
- Spin orbit interaction induced magnetic dynamics
- Time: 4:00 pm
- Place: 474 Chamberlin Hall
- Speaker: Luqiao Liu, IBM TJ Watson Research Center
- Abstract: Controlling magnetic orientation in a fast and energy-efficient way is both fundamentally important and has profound technical implications. Conventional ways of switching magnetic moment include employing magnetic fields from current-carrying coil and using the spin transfer torque effect from spin valve structures. Recent studies show that spin orbit interaction induced phenomena, such as the spin Hall effect and spin momentum locking in topological insulators, can provide effective mechanisms to generate spin currents and to control the orientation of nano-magnets. In this talk, I will discuss various magnetic dynamics that can be excited using spin orbit interactions, including ferromagnetic resonance, reversible magnetic switching and persistent magnetic oscillations. Compared with conventional spin torque devices, a higher current-spin conversion efficiency and lower energy dissipation are exhibited in those experiments. Besides, I will also talk about experimental approaches that can be utilized to identify the origin and quantify the strength of those effects. With the information gained in those studies, further improvement on the spin generation efficiency can be expected.
- Host: Coppersmith