1. PH427 Journal Club Presentation Matt W. Graham March 3, 2015 PH427 Journal Club Presentation Matt W. Graham March 3, 2015

2. Motivation E(k)E(k) TeTe ThTh  T. Mueller et al., Nature Photonics 4, 297-301 (2010). Graphene Photodetector Fundamental Physics How do electrons in graphene loose their energy? Possible applications graphene bolometers and photosensors designing graphene electronics

3. < 4 meV Electron and acoustic phonon velocity mismatch slows cooling 1-2 How do electrons relax in graphene? 200 m eV Acoustic phonons or optical phonons?

4. < 4 meV Electron and acoustic phonon velocity mismatch slows cooling 1-2 Relationship with class material How do electrons relax in graphene? 200 m eV Acoustic phonons or optical phonons? 200 meV

5. kBTekBTe Supercollision acoustic phonon relaxation q ac v s q disorder kBTekBTe Fast

6. Result From Paper: supercollison acoustic model predict how electrons relax Conclusions: a new model and physical process of how electrons relax in graphene has been developed