The focus of condensed matter and materials physics (CMMP) is understanding
how underlying laws unfold in the physical world around us. A typical
system consists of many individual particles or units which have coalesced
into a medium with new, often surprising, properties. Superconductors
and liquid crystals are two classic examples. In recent years, CMMP has
grown to be tremendously broad. Topics being actively pursued include,
for instance, strong correlations between electrons in novel materials,
quantum phenomena in low dimensional systems, phases and dynamics of
soft matter, quantum phase transitions, far from equilibrium phenomena,
and granular materials. Here at Duke, we focus on two areas of condensed
matter and materials physics: **quantum phenomena in nanometer scale
systems**, and **nonlinear and complex systems**.

Experiments on these topics are typically carried out by individual students who have the opportunity to explore all aspects of a project, including design, construction, and data analysis. Theoretical progress relies on the adaptation and extension of many-body theory and dynamical systems theory, distilling the crucial features of the system into models that can be studied either analytically or numerically.

Fundamental interest in nanophysics -- the physics of small, nanometer scale, bits of solid -- stems from the ability to control and probe systems on length scales larger than atoms but small enough that the averaging inherent in bulk properties has not yet occurred. Using this ability, entirely unanticipated phenomena can be uncovered on the one hand, and the microscopic basis of bulk phenomena can be probed on the other. Additional interest comes from the many links between nanophysics and nanotechnology. Key issues currently in nanophysics include how novel quantum collective behavior emerges from simple elements, connections to quantum information (entanglement), and the role of topological states in a variety of settings. For descriptions of particular projects, see the webpages arranged by faculty (Baranger, Chandrasekharan, Chang, Finkelstein, Hastings, and Teitsworth).

The challenge in this area is to discover and characterize the collective behavior of complex systems, and to uncover the principles that connect the physics and logic of interactions between parts to the properties of the full system. This rapidly developing research area relies heavily on the concepts and language of nonlinear dynamics, and the evolution of this area of research at Duke began with physicists, geophysicists, mathematicians, and engineers recognizing they shared a common language. For descriptions of particular projects, see the webpages arranged by faculty (Behringer, Palmer, Socolar, and Teitsworth).

Baranger: | Theory of quantum phenomena at the nanometer scale; many-body effects in quantum dots and wires; conduction through single molecules; quantum computing; quantum phase transitions. |

Behringer: | Experiments on instabilities and pattern formation in fluids; flow, jamming, and stress patterns in granular materials. |

Chandrasekharan: | Theoretical studies of quantum phase transitions using quantum Monte Carlo methods; lattice QCD (see nuclear and particle theory page). |

Chang: | Experiments on quantum transport at low temperature; one-dimensional superconductivity; dilute magnetic semiconductor quantum dots; Hall probe scanning. |

Finkelstein: | Experiments on quantum transport at low temperature; carbon nanotubes; Kondo effect; cryogenic scanning microscopy; self-assembled DNA templates. |

Hastings: | Mathematical physics; topological order; quantum information theory; computational methods. |

Palmer: | Theoretical models of learning and memory in neural networks; glassy dynamics in random systems with frustrated interactions. |

Socolar: | Theory of dynamics of random networks with applications to gene regulation; stress patterns in granular materials; tiling theory and quasicrystals. |

Teitsworth: | Experiments on nonlinear dynamics of currents in semiconductors. |