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arXiv · hep-th/0701001

Flavoured Large N Gauge Theory in an External Magnetic Field

Veselin G. Filev·Clifford V. Johnson·R. C. Rashkov·K. S. Viswanathan
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Abstract

We consider a D7-brane probe of AdS$_{5}\times S^5$ in the presence of pure gauge $B$-field. In the dual gauge theory, the $B$-field couples to the fundamental matter introduced by the D7-brane and acts as an external magnetic field. The $B$-field supports a 6-form Ramond-Ramond potential on the D7-branes world volume that breaks the supersymmetry and enables the dual gauge theory to develop a non-zero fermionic condensate. We explore the dependence of the fermionic condensate on the bare quark mass $m_{q}$ and show that at zero bare quark mass a chiral symmetry is spontaneously broken. A study of the meson spectrum reveals a coupling between the vector and scalar modes, and in the limit of weak magnetic field we observe Zeeman splitting of the states. We also observe the characteristic $\sqrt{m_{q}}$ dependence of the ground state corresponding to the Goldstone boson of spontaneously broken chiral symmetry.

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Veselin G. Filev, Clifford V. Johnson, R. C. Rashkov, K. S. Viswanathan. 2007-06-29. Flavoured Large N Gauge Theory in an External Magnetic Field. https://doi.org/10.1088/1126-6708%2F2007%2F10%2F019

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