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

The magnetization ripple: a nonlocal stochastic PDE perspective,
arXiv:1709.01374   (with F. Otto) [pdf]

On the uniqueness of minimisers of Ginzburg-Landau functionals,
arXiv:1708.05040  
(with L. Nguyen, V. Slastikov, A. Zarnescu) [pdf]
 

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,
arXiv:1706.01281v2 (with X. Lamy)    [pdf]


Publications

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]


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

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

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]

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]

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

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]

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

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]

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]


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]

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]
 
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]


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

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

Singularities of divergence-free vector fields with values into S^1 or S^2. Applications to micromagnetics, 

Confluentes Mathematici 4 (2012), 1-80   [pdf]

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

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

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]

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

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

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

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]

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]

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

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]

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

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] 

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

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 ] 

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

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

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

 

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


Reports
 
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] 


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


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


Publications in Romanian Journals


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)


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


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


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