Emergent quasi-particles and gauge fields in quantum matter

Unfortunately, there is a paucity of good review articles that give gentle introductions to current research in condensed matter, both for beginning graduate students and for curious non-experts. Too many reviews are exhaustive, in both senses of the word! Contemporary Physics is a journal that aims to address this problem. I should look at it more often. In 2009, there was a nice 50th-anniversary issue, featuring some significant articles, with retrospective commentary. For example, there is a fascinating article about Snow Crystals by F.C. Franks.

My UQ colleague, Ben Powell recently submitted a nice review to the journal.

Emergent particles and gauge fields in quantum matter 
I give a pedagogical introduction to some of the many particles and gauge fields that can emerge in correlated matter. The standard model of materials is built on Landau's foundational principles: adiabatic continuity and spontaneous symmetry breaking. These ideas lead to quasiparticles that inherit their quantum numbers from fundamental particles, Nambu-Goldstone bosons, the Anderson-Higgs mechanism, and topological defects in order parameters. I then describe the modern discovery of physics beyond the standard model. Here, quantum correlations (entanglement) and topology play key roles in defining the properties of matter. This can lead to fractionalised quasiparticles that carry only a fraction of the quantum numbers that define fundamental particles. These particles can have exotic properties: for example Majorana fermions are their own antiparticles, anyons have exchange statistics that are neither bosonic nor fermionic, and magnetic monopoles do not occur in the vacuum. Gauge fields emerge naturally in the description of highly correlated matter and can lead to gauge bosons. Relationships to the standard model of particle physics are discussed.
 

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