My habilitation thesis "Singularités des champs de vecteurs à divergence nulle et à valeurs dans S^1 ou S^2.
Applications en micromagnétisme" can be downloaded   [HERE]

Preprints

1. A short proof of the C^{1,1} regularity for the eikonal equation, arXiv:2409.05204. [pdf]

2. Minimality of vortex solutions to Ginzburg-Landau type systems for gradient fields in the unit ball in dimension N ≥ 4, arXiv:2310.11384 (with M. Nahon, L. Nguyen) [pdf]

Publications

53. Renormalised energy between boundary vortices in thin-film micromagnetics with Dzyaloshinskii-Moriya interaction, Nonlinear Anal. 250 (2025), Paper No. 113622 (with F. L'Official) [pdf]

52. Vortex sheet solutions for the Ginzburg-Landau system in cylinders: symmetry and global minimality,
Calc. Var. Partial Differential Equations 63 (2024), 20 pp. (with M. Rus) [pdf]

51. Local minimality of R^N -valued and S^N -valued Ginzburg–Landau vortex solutions in the unit ball B^N,
Ann. Inst. H. Poincaré, Anal. Non linéaire 41 (2024), no. 3, 663–724 (with L. Nguyen) [pdf]

50. An effective model for boundary vortices in thin-film micromagnetics,
Math. Models Methods Appl. Sci. 33 (2023), 1929-1973. (with M. Kurzke) [pdf]

49. Asymptotic stability of precessing domain walls for the Landau-Lifshitz-Gilbert equation in
a nanowire with Dzyaloshinskii-Moriya interaction, Comm. Math. Phys. 401 (2023), 2901-2957 (with R. Cote)    [pdf]

48. Variational methods for a singular SPDE yielding the universality of the magnetization ripple,
Comm. Pure Appl. Math. 76 (2023), 2959-3043. (with F.Otto, T. Ried, P. Tsatsoulis) [pdf]

47. Uniqueness result for a weighted pendulum equation modeling domain walls in notched ferromagnetic nanowires,
C. R. Math. Acad. Sci. Paris 360 (2022), 819-828 [pdf]

46. Separation of domain walls with nonlocal interaction and their renormalised energy
by Γ-convergence in thin ferromagnetic films, J. Differential Equations 339 (2022), 395-475 (with R. Moser) [pdf]

45. Renormalized energy between vortices in some Ginzburg-Landau models
on 2-dimensional Riemannian manifolds, Arch. Ration. Mech. Anal. 239 (2021), 1577–1666  (with R. Jerrard) [pdf]

44. Global Jacobian and Gamma-convergence in a two-dimensional Ginzburg-Landau model for boundary vortices,
J. Funct. Anal. 280 (2021), 66pp  (with M. Kurzke) [pdf]

43. Symmetry and multiplicity of solutions in a two-dimensional Landau-de Gennes model for liquid crystals,
Arch. Ration. Mech. Anal. 237 (2020),  1421-1473  (with L. Nguyen, V. Slastikov, A. Zarnescu) [pdf]

42. A DeGiorgi type conjecture for minimal solutions to a nonlinear Stokes equation,
Comm. Pure Appl. Math. 73 (2020), 771-854 (with A. Monteil) [pdf]

41. On the uniqueness of minimisers of Ginzburg-Landau functionals,
Ann. Sci. Éc. Norm. Supér. 53 (2020), 589-613  (with L. Nguyen, V. Slastikov, A. Zarnescu) [pdf]

40. Global uniform estimate for the modulus of 2D Ginzburg-Landau vortexless solutions
with asymptotically infinite boundary energy, 
SIAM J. Math. Anal. 52 (2020), 524-542 (with M. Kurzke and X. Lamy) [pdf]

39. A necessary condition in a De Giorgi type conjecture for elliptic systems in infinite strips,
accepted in the volume dedicated to Haim Brezis on the occasion of his 75th birthday,
Pure and Applied Functional Analysis 5 (2020), 981-999 (with A. Monteil) [pdf]

38. Dimension reduction and optimality of the uniform state in a Phase-Field-Crystal model
involving a higher order functional,
J. Nonlinear Sci. 30 (2020), 261-282  (with H. Zorgati) [pdf]

37. Energy minimisers of prescribed winding number in an S^1-valued nonlocal Allen-Cahn type model,
Adv. Math. 357 (2019), 45 pp. (with Roger Moser) [pdf]

36. Lifting of RP^{d-1}-valued maps in BV and applications to uniaxial Q-tensors.
With an appendix on an intrinsic BV-energy for manifold-valued maps,
Calc. Var. Partial Differential Equations 58 (2019), no. 2, 26 pp (with X. Lamy)    [pdf]

35. The magnetization ripple: a nonlocal stochastic PDE perspective,
J. Math. Pures Appl. (9) 130 (2019), 157-199  (with F. Otto) [pdf]

34. Uniqueness of degree-one Ginzburg-Landau vortex in the unit ball in dimensions N ≥ 7
C. R. Math. Acad. Sci. Paris 356 (2018), 922-926  (with L. Nguyen, V. Slastikov, A. Zarnescu) [pdf]

33. Néel walls with prescribed winding number and how a nonlocal term can change the energy landscape,
 J. Differential Equations 263 (2017), 5846–5901   (with R. Moser)    [pdf]

32. Interaction energy between vortices of vector fields on Riemannian surfaces,
C. R. Math. Acad. Sci. Paris 355 (2017), 515–521 (with R. Jerrard)   [pdf]

31. Kinetic formulation of vortex vector fields,
Anal. PDE 10 (2017), 729–756  (with P. Bochard)    [pdf]

30. Stability of point defects of degree ±1/2 in a two-dimensional nematic liquid crystal model,
Calc. Var. Partial Differential Equations  55 (2016), 33pp   (with L. Nguyen, V. Slastikov, A. Zarnescu)     [pdf]

29. Interaction energy of domain walls in a nonlocal Ginzburg-Landau type model from micromagnetics,
Arch. Ration. Mech. Anal. 221 (2016), 419-485 (with R. Moser)     [pdf]

28. Asymmetric domain walls of small angle in soft ferromagnetic films,
Arch. Ration. Mech. Anal. 220 (2016), 889-936 (with L. Doering)     [pdf]

27. Instability of point defects in a two-dimensional nematic liquid crystal model,
Ann. Inst. H. Poincaré, Anal. Non linéaire 33 (2016), 1131–1152 (with L. Nguyen, V. Slastikov, A. Zarnescu)     [pdf]

26. A regularizing property of the 2D-eikonal equation,
Comm. Partial Differential Equations 40 (2015), 1543–1557  (with C. De Lellis)     [pdf]

25. Stability of the melting hedgehog in the Landau-de Gennes theory of nematic liquid crystals
Arch. Ration. Mech. Anal. 215 (2015), 633–673 (with L. Nguyen, V. Slastikov, A. Zarnescu)  [pdf]

24. A reduced model for domain walls in soft ferromagnetic films at the cross-over from symmetric to asymmetric wall types,
J. Eur. Math. Soc. (JEMS) 16 (2014), 1377–1422.(with L. Döring, F. Otto)  [pdf]

23. Uniqueness results for an ODE related to a generalized Ginzburg-Landau model for liquid crystals,
SIAM Journal on Mathematical Analysis 46 (2014), 3390–3425 (with L. Nguyen, V. Slastikov, A. Zarnescu)  [pdf]

22. A thin-film limit in the Landau-Lifshitz-Gilbert equation relevant for the formation of Néel walls,
The Haim Brezis Festschrift, J. Fixed Point Theory Appl. 15 (2014) 241–272 (with R. Cote, E. Miot)  [pdf]
 
21. Stability of the vortex defect in the Landau–de Gennes theory for nematic liquid crystals,
C.R. Acad. Sci. Paris, Ser. I 351 (2013) 533–537  (with L. Nguyen, V. Slastikov, A. Zarnescu)     [pdf]

20. Two-dimensional unit-length vector fields of vanishing divergence, 
J. Funct. Anal. 262 (2012), 3465–3494     [pdf]

19. A zigzag pattern in micromagnetics,
 J. Math. Pures Appl. 98 (2012), 139-159. (with R. Moser)     [pdf]

18. Singularities of divergence-free vector fields with values into S^1 or S^2. Applications to micromagnetics, 
Confluentes Mathematici 4 (2012), 1-80   [pdf]

17. Entropy method for line-energies,
Calc. Var. Partial Differential Equations 44 (2012), 375-418 (with B. Merlet)     [pdf]

16. Gradient vector fields with values into S^1, 
C.R. Acad. Sci. Paris, Ser. I 349 (2011), 883-887   [pdf]

15. A compactness result for Landau state in thin-film micromagnetics,
Ann. Inst. H. Poincaré, Anal. Non linéaire 28(2011), 247-282 (with F. Otto)    [pdf]

14. Lower bound for the energy of Bloch walls in micromagnetics,
Arch. Ration. Mech. Anal. 199 (2011), 369-406   (with B. Merlet)  [pdf]

13. Vortex energy and 360° Néel walls in thin films micromagnetics,
Comm. Pure Appl. Math. 63 (2010), 1677-1724  (with H. Knüpfer)    [pdf]

12. A Gamma-convergence result for Néel walls in micromagnetics,
Calc. Var. Partial Differential Equations 36 (2009), 285-316.   [pdf]

11. A survey of some new results in ferromagnetic thin films,
Séminaire d'Équations aux Dérivées Partielles (Ecole Polytechnique) 2007--2008,  Exp. No. VI, 19 pp.  [pdf]

10. A compactness result in thin-film micromagnetics and the optimality of the Néel wall,
J. Eur. Math. Soc. (JEMS)  10 (2008), 909-956.   (with F. Otto)     [pdf]

9. Pohozaev type identities for an elliptic equation ,
CRM Proceedings and Lecture Notes, 44 (2008), 75-88    [pdf] 

8. On the relation between minimizers of a Gamma-limit energy and optimal lifting in BV-space ,
Commun. Contemp. Math 9 (2007), 447-472    (with A. Poliakovsky)     [pdf]

7. Energy expansion and vortex location for a two dimensional rotating Bose-Einstein condensate,
 Rev. Math. Phys. 18 (2006), 119--162     (with V. Millot)     [pdf] 

6. The critical velocity for vortex existence in a two dimensional rotating Bose-Einstein condensate,
J. Funct. Anal. 233(2006), 260-306     (with V. Millot)     [pdf] 

5. Vortices in a 2d rotating Bose-Einstein condensate,
C.R. Acad. Sci. Paris, Ser.I 340(2005), 571-576     (with V. Millot)     [pdf] 

4. The space BV(S^2,S^1) : minimal connection and optimal lifting,
Ann. Inst. H. Poincaré, Anal. Non linéaire 22(2005), 283-302 [pdf, ps ] 

3. Optimal lifting for BV(S^1,S^1),
Calc. Var. Partial Differential Equations 23(2005), 83-96     [pdf] 

2. On an open problem about how to recognize constant functions,
Houston Journal of Mathematics 31(1), 2005, 285-304     [pdf] 

1. Lifting of BV functions with values in S^1,
C.R. Acad. Sci. Paris, Ser.I 337 (2003), 159-164 (with J. Davila)     [pdf] 

Book

 1. Singularities in some variational problems,
VDM Verlag Dr. Müller, Saarbrücken, 2010, 260pp  [pdf] [cover_book] .


Reports
 
5. A De Giorgi type conjecture for elliptic systems under the divergence constraint,
Oberwolfach Reports, Volume 22/2020 (Calculus of Variations: A. Figalli, R.V. Kohn, T.Toro, N. Wickramasekera).    [pdf] 

4. Some uniqueness results for minimisers of Ginzburg-Landau functionals,
Oberwolfach Reports, Volume 20/2018 (Nonlinear Data: Theory and Algorithms)  [pdf]
 
3. Interaction energy of domain walls of logarithmically decaying tails in a nonlocal variational model,
Oberwolfach Reports, Volume XX/2016 (Calculus of Variations: S. Brendle, A. Figalli, R. Jerrard, N. Wickramasekera).    [pdf] 

2. Le prix Henri Poincaré pour Sylvia Serfaty,
Gaz. Math. 135 (2013), 51–56 (with B. Helffer)  [pdf] 

1. Pattern formation in micromagnetics,
Oberwolfach Reports, Volume 36/2012 (Calculus of Variations: C. De Lellis, G. Huisken, R. Jerrard).    [pdf] 

Publications in Romanian Journals

4. Hamilton-Jacobi Equations and Optimal Control , Proceedings of the International Conference on Nonlinear Operators, Differential Equations and Applications, Cluj-Napoca, 2001, Seminar on fixed point theory Cluj-Napoca, 3/2002, 239-248  (with A. Basson)

3. Sur les Conjectures de Markus-Yamabe et de la Jacobienne , Séminaire de la Theorie de la Meilleure Approximation, Convexite et Optimisation, Ed. Srima (2000), 125-141

2. About an interesting sequence, Octogon, 1/2000, 173-180

1. A generalization of convex and midconvex functions, Analysis, Functional equations, Approximation and Convexity, Proceedings of the Conference Held in Honor of Professor Elena Popoviciu on the Occasion of her 75th Birthday, Ed. Carpatica (1999), 89-93