1 / 22

Quantum complexity in condensed matter physics

Quantum complexity in condensed matter physics. S Julian University of Toronto. Emergent properties Particle behaviour of fluctuating modes Broken symmetry and rigidity Indirect interaction. Condensed Matter Physics. Fundamental Physics. Applied Physics.

brody
Download Presentation

Quantum complexity in condensed matter physics

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Quantum complexity in condensed matter physics S Julian University of Toronto • Emergent properties • Particle behaviour of fluctuating modes • Broken symmetry and rigidity • Indirect interaction

  2. Condensed Matter Physics Fundamental Physics Applied Physics -Quantum properties of many body systems -Noise (eg in electronic circuits) -Novel soft matter, elasticity and viscosity -Modeling the universe -memory devices for computers -processors for computers -corrosion and catalysis -superconducting devices Elementary particle physics energy Condensed matter physics biology time

  3. Combinatorial chemistry vs. emergent properties

  4. Empty boxes are more interesting than people think! • At 0K: zero point motion • At high T: electrons and • positrons are created • At Low T: black-body radiation

  5. Analogy with quantum condensed matter physics: • At 0K: zero point motion • of phonon, electron-hole pairs, etc. • At high T: electrons and • positrons are created • At Low T: black-body radiation • Real phonons and electrons+holes

  6. Dispersion relations for (quasi)particles

  7. How to make a metal

  8. Conventional phase transition: broken symmetry states

  9. Conventional phase transition Spontaneous symmetry breaking The susceptibility diverges > rigidity

  10. Mass enhancement Magnetic pairing

  11. Indirect interactions: - One of the central principles of physics

  12. Unusual “particle-like” excitations are possible in condensed matter systems Overdamped modes Propagating modes

  13. The quantum critical point Fe Cu At Tc, fluctuations diverge

  14. quantum critical superconductivity?

  15. CePd2Si2 phase diagram

  16. Methodology of condensed matter physics: • Crystal growth: • Crystals are to us what stars are to astronomers • Scattering: • A good way to find out what is inside something is to throw something at it and see how it bounces off • Nano-physics: • Scanning tunneling microscopy, point contact spectroscopy, etc. • Low temperatures and high magnetic fields: • Dilution refrigeration

  17. Anvil pressure cells

  18. Phase diagram of Ca2RuO4 Antiferromagetic insulator Temperature / K Ferromagnetic metal Pressure / kbar

  19. Structural transitions

  20. Atomic orbitals in crystals

  21. Orbital ordering

  22. Summary • The fundamental principles of quantum condensed matter physics are: • Emergent properties: new kinds of ‘particles’ emerge as complexity increases • Broken symmetry and rigidity • Indirect interactions The methodology focuses on crystal growth, scattering and low temperatures.

More Related