Research and main results: my work stands at the boundary between field theory and condensed matter physics. My main activity is to use renormalization group techniques and, in particular, nonperturbative renormalization group techniques, in order to elucidate the critical, and more generally the long distance, behaviour of systems coming from statistical, condensed matter, and soft matter physics. I have mainly worked on three different kinds of situations:
 magnetic systems with competing interactions, also named frustrated magnets
 polymerized membranes including isotropic, tubular, disordered membranes
 disordered magnets like diluted Ising model, random field and random anisotropy systems
In all these systems the perturbative approaches have encountered great difficulties to describe the long distance, low energy, physics while nonperturbative techniques, in the form developped by C. Wetterich in the 90's and following the seminal work of K.G. Wilson in the 70's, have been sucessfully used and have allowed to clarify both qualitatively and quantitatively many intriguing situations.
Publications

[1] LowTemperature Properties of TwoDimensional Frustrated Quantum Antiferromagnets: P. Azaria, B. Delamotte and D. Mouhanna, Phys. Rev. Lett. 68, 1762 (1992).
[2] LowTemperature Properties of TwoDimensional Frustrated Quantum Antiferromagnets: P. Azaria, B. Delamotte and D. Mouhanna, Helvetica Physica Acta 65, 458 (1992).
[3] Spin Stiffness of Canted Antiferromagnets: P. Azaria, B. Delamotte, T. Jolicoeur and D. Mouhanna, Phys. Rev. B 45, 12612 (1992).
[4] Spontaneous symmetry breaking in quantum frustrated antiferromagnets: P. Azaria, B. Delamotte and D. Mouhanna, Phys. Rev. Lett. 70, 2483 (1993).
[5] Symmetry breaking and finite size scaling in antiferromagnets: P. Azaria, B. Delamotte and D. Mouhanna, J. de Phys. 3, 291 (1993).
[6] Monte Carlo calculation of the spin stiffness of the twodimensional Heisenberg model: M. Caffarel, P. Azaria, B. Delamotte and D. Mouhanna, Europhysics Letters 26, 493 (1994).
[7] The Massive CP_{N} Model for frustrated spin systems: P. Azaria, P. Lecheminant and D. Mouhanna, Nuclear Physics B 455, 648 (1995).
[8] Wilsonrenormalizationgroup approach of the principal chiral model around two dimensions: B. Delamotte, D. Mouhanna and P. Lecheminant, Phys. Rev. B 59, 6006 (1999).
[9] Correlated Fermions in a OneDimensional Quasiperiodic Potential: J. Vidal, D. Mouhanna and T. Giamarchi, Phys. Rev. Lett. 83, 3908 (1999).
[10] Frustrated Heisenberg Magnets: A Nonperturbative Approach : M. Tissier, B. Delamotte and D. Mouhanna Phys. Rev. Lett. 84, 5208 (2000).
[11] Nonperturbative approach to the principal chiral model between two and four dimensions: M. Tissier, D. Mouhanna and B. Delamotte, Phys. Rev. B 61, 15327 (2000).
[12] An exact renormalization group approach to frustrated magnets: M. Tissier, D. Mouhanna and B. Delamotte, Int. J. Mod. Phys. A16, 2131 (2001).
[13] Spinstiffness and topological defects in twodimensional frustrated spin systems: M. Caffarel, P. Azaria, B. Delamotte and D. Mouhanna, Phys. Rev. B 64, 014412/1 (2001).
[14] Interactions in quasicristals : J. Vidal, D. Mouhanna and T. Giamarchi, Int. J. Mod. Phys. B15, 1329 (2001).
[15] Interacting fermions in selfsimilar potentials: J. Vidal, D. Mouhanna and T. Giamarchi, Phys. Rev. B 65, 014201101420115 (2002).
[16] The randomly dilute Ising model: a nonperturbative approach: M. Tissier, D. Mouhanna, J. Vidal and B. Delamotte, Phys. Rev. B 65 1404021 (2002).
[17] XY frustrated systems: continuous exponents in discontinuous phase transitions: M. Tissier, B. Delamotte and D. Mouhanna, Phys. Rev. B 67, 1344221 (2003).
[18] Optimization of the derivative expansion in the nonperturbative renormalization group L. Canet, B. Delamotte, D. Mouhanna, J. Vidal, Phys. Rev. D 67, 0650041 (2003).
[19] Nonperturbative renormalization group approach to the Ising model : A derivative expansion at order 4: L. Canet, B. Delamotte, D. Mouhanna et J. Vidal, Phys. Rev. B 68, 0644211 (2003)
[20] Nonperturbative renormalization group approach to frustrated magnets: B. Delamotte, D. Mouhanna, M. Tissier, Phys. Rev. B 69 134413 (2004)
[21] Fustrated magnets in three dimensions: a nonperturbative approach: B. Delamotte, D. Mouhanna, M. Tissier, J. Phys. :Condens. Matter 16 s883 (2004)
[22] Critical properties of a continuous family of XY noncollinear magnets : A. Peles, B.W. Southern, B. Delamotte, D. Mouhanna and M. Tissier, Phys. Rev. B 69, 2204081(R) (2004).
[23] Shorttime dynamics of a family of XY noncollinear magnets: S. Bekhechi, B.W. Southern, A. Peles, and D. Mouhanna; Phys. Rev. E 74, 016109 (2006).[24] Fixed points in frustrated magnets revisited ” : B. Delamotte, Y. Holovatch, D. Ivaneyko, D. Mouhanna and M. Tissier, J. Stat. Mech. (2008) P03014.
[25] Crumpling transition and flat phase of polymerized phantom membranes : J.P. Kownacki and D. Mouhanna, Phys. Rev. E 79, 040101 (2009).
[26] Spontaneous versus explicit replica symmetry breaking in the theory of disordered systems : D. Mouhanna and G. Tarjus, Phys. Rev. E 81, 051101 (2010).
[27] Relevance of the fixed dimension perturbative approach to frustrated magnets in two and three dimensions : B. Delamotte, M. Dudka, Yu. Holovatch, and D. Mouhanna, Phys. Rev. B 82, 104432 (2010).
[28] Analysis of the 3d massive renormalization group perturbative expansions : a delicate case : B. Delamotte, M. Dudka, Yu. Holovatch, and D. Mouhanna, Condens. Matter Phys. 13, 43703 (2010).
[29] Crumpledtotubule transition in anisotropic polymerized membranes : beyond epsilonexpansion: K. Essafi, J.P. Kownacki and D. Mouhanna, Phys. Rev. Lett. 106, 128102 (2011).
[29] Nonperturbative renormalization group : basic principles and some applications : D. Mouhanna, B. Delamotte, J.P. Kownacki, M. Tissier, Mod. Phys. Lett. B, 25, 873 (2011).
[30] Nonperturbative renormalization group approach to Lifshitz critical behaviour: K. Essafi, J.P. Kownacki and D. Mouhanna, EPL, 98 (2012) 51002.
[31] Firstorder phase transitions in polymerized phantom membranes: K. Essafi, J.P. Kownacki and D. Mouhanna, Phys. Rev. E 89, 042101 (2014).