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arXiv · hep-th/0611099

Holographic phase transitions at finite baryon density

Shinpei Kobayashi·David Mateos·Shunji Matsuura·Robert C. Myers·Rowan M. Thomson
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Abstract

We use holographic techniques to study SU(Nc) super Yang-Mills theory coupled to Nf << Nc flavours of fundamental matter at finite temperature and baryon density. We focus on four dimensions, for which the dual description consists of Nf D7-branes in the background of Nc black D3-branes, but our results apply in other dimensions as well. A non-zero chemical potential mu or baryon number density n is introduced via a nonvanishing worldvolume gauge field on the D7-branes. Ref. [1] identified a first order phase transition at zero density associated with `melting' of the mesons. This extends to a line of phase transitions for small n, which terminates at a critical point at finite n. Investigation of the D7-branes' thermodynamics reveals that (d mu / dn)_T <0 in a small region of the phase diagram, indicating an instability. We comment on a possible new phase which may appear in this region.

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Shinpei Kobayashi, David Mateos, Shunji Matsuura, Robert C. Myers, Rowan M. Thomson. 2007-02-07. Holographic phase transitions at finite baryon density. https://doi.org/10.1088/1126-6708%2F2007%2F02%2F016

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