Research Paper 

29. J. Byeon, N. Ikoma, A. Malchiodi and L. Mari

Existence and regularity for prescribed Lorentzian mean curvature hypersurfaces, and the Born–Infeld model.

Annals of PDE 10 (2024), no. 1, Paper No. 4. (arXiv:2112.11283 [math.AP]).

28. N. Ikoma and M. Yamanobe

The existence and multiplicity of $L^2$-normalized solutions to nonlinear Schrödinger equations with variable coefficients. 

Advanced Nonlinear Studies 24(2024), no.2, Paper No. 477.

27.  S. Hasegawa, N. Ikoma and T. Kawakami

On weak solutions to a fractional Hardy-Hénon equation: Part II: Existence.

Nonlinear Analysis Volume 227, February 2023, 113165 (arXiv:2102.05873v1 [math.AP]).

26. S. Adachi, N. Ikoma and T. Watanabe

      Existence and asymptotic behavior of positive solutions for a class of locally superlinear Schrödinger equation.

      Manuscripta Mathematica 172 (2023), 933-970 (arXiv:2201.04246 [math.AP]). 

25. N. Ikoma and Y. Miyamoto

The compactness of minimizing sequences for a nonlinear Schroedinger system with potentials.

Communications in Contemporary Mathematics 25 (2023), No. 02, 2150103  (arXiv:2010.14722 [math.AP]).

24. N. Ikoma

On the existence of positive solutions to a certain class of semilinear elliptic equations. 

SN Partial Differential Equations  and Applications 2, Article number: 28 (2021).

23. S. Hasegawa, N. Ikoma and T. Kawakami

On weak solutions to a fractional Hardy-Hénon equation: Part I: Nonexistence. 

Communications on Pure & Applied Analysis  20 (2021), no. 4, 1559–1600 (arXiv:2004.09747v1 [math.AP]). 

22. N. Ikoma, K. Tanaka, Z.Q. Wang and C. Zhang

Nonlinear elliptic equations of sublinearity: qualitative behavior of solutions.

Indiana University Mathematics Journal 71 (2022), no. 5, 2001-2043.

21. N. Ikoma, K. Tanaka, Z.Q. Wang and C. Zhang

Semi-classical states for logarithmic Schroedinger equations.

Nonlinearity  34 (2021), no. 4, 1900–1942. 

20. N. Ikoma

Multiplicity of radial and nonradial solutions to equations with fractional operators. 

Communications on Pure & Applied Analysis 19 (2020), no.7, 3501-3530  (arXiv:1902.02029 [math.AP]). 

19. N. Ikoma and Y. Miyamoto

Stable standing waves of nonlinear Schroedinger equations with potentials and general nonlinearities. 

Calculus of Variations and Partial Differential Equations 59, Issue 2, Article number: 48 (2020).

18. N. Ikoma and K. Tanaka

A note on deformation argument for L^2 normalized solutions of nonlinear Schroedinger equations and systems. 

Advances in Differential Equations 24 (2019), no. 11-12, 609-646 (arXiv:1902.02028 [math.AP]).

17. T. Akahori, S. Ibrahim, N. Ikoma, H. Kikuchi and H. Nawa

Uniqueness and nondegeneracy of ground states to nonlinear scalar field equations involving 

the Sobolev critical exponent in their nonlinearities for high frequencies. 

Calculus of Variations and Partial Differential Equations 58 (2019), Issue 4, Article: 120(arXiv:1801.08696 [math.AP])

16. N. Ikoma, A. Malchiodi and A. Mondino

Foliation by area-constrained Willmore spheres near a non-degenerate critical point of the scalar curvature. 

International Mathematics Research Notices (IMRN) 2020, Issue 19, 6539–6568 (arXiv:1806.00390 [math.DG]).

15. P. Felmer and N. Ikoma

 Existence and nonexistence of positive solutions to some fully nonlinear equation in one dimension. 

Journal of Functional Analysis 275 (2018), no. 8, 2162-2196.

14. N. Ikoma, M. Ishiwata and H. Wadade

Existence and non-existence of maximizers for the Moser-Trudinger type inequalities under inhomogeneous constraints. 

Mathematische Annalen 373 (2019), no. 1-2, 831-851.

13. N. Ikoma, A. Malchiodi and A. Mondino, 

Embedded area-constrained Willmore tori of small area in Riemannian three-manifolds II: Morse Theory 

American Journal of Mathematics 139 (2017), no. 5, 1315-1378. 

12. N. Ikoma, A. Malchiodi and A. Mondino

Embedded area-constrained Willmore tori of small area in Reimannian three-manifolds I: Minimization. 

Proceedings of the London Mathematical Society (3) 115 (2017), no. 3, 502-544.

11. N. Ikoma

Existence of solutions of scalar field equations with fractional operator.

Journal of Fixed Point Theory and Applications 19 (2017), no. 1, 649-690.

Erratum to: Existence of solutions of scalar field equations with fractional operator. 

Journal of Fixed Point Theory and Applications 19 (2017), no. 2, 1649-1652.

10. N. Ikoma and H. Ishii

Eigenvalue problem for fully nonlinear second-order elliptic PDE on balls, II.

Bulletin of Mathematical Sciences 5 (2015), no. 3, 451-510.

9. N. Ikoma

Existence of ground state solutions to the nonlinear Kirchhoff type equations with potential.

Discrete and Continuous Dynamical System - Series A 35 (2015), no. 3, 943-966.

8. G.M. Figueiredo, N. Ikoma and J.R. Santos Junior

Existence and concentration result for the Kirchhoff type equations with general nonlinearities.

Archive for Rational Mechanics and Analysis 213 (2014), no. 3, 931-979.

7. N. Ikoma

On compactness of minimizing sequences to nonlinear Schrödinger systems under multiconstraint condition.

Advanced Nonlinear Studies 14 (2014), no. 1, 115-136.

6. N. Ikoma and H. Ishii

Eigenvalue problem for fully nonlinear second-order elliptic PDE on balls.

Annales de l'Institut Henri Poincaré. Analyse Non Linéaire 29 (2012), no. 5, 783-812.

5. N. Ikoma

On radial solutions of inhomogeneous nonlinear scalar field equations.

Journal of Mathematical Analysis and Applications 386 (2012), no. 2, 744-762.

4. N. Ikoma and K. Tanaka

A local mountain pass type result for a system of nonlinear Schrödinger equations.

Calculus of Variations and Partial Differential Equations 40 (2011), no. 3-4, 449-480.

3. J. Hirata, N. Ikoma and K. Tanaka

Nonlinear scalar field equations in R^N: mountain pass and symmetric mountain pass approaches.

Topological Methods in Nonlinear Analysis 35 (2010), no. 2, 253-276.

2. N. Ikoma

Existence of standing waves for coupled nonlinear Schrödinger equations.

Tokyo Journal of Mathematics 33 (2010), no. 1,  89-116.

1. N. Ikoma

Uniqueness of Positive Solutions for a Nonlinear Elliptic System.

Nonlinear Differential Equations and Applications NoDEA 16 (2009), no. 5, 555-567.

Proceeding (With Peer-Review)

1. N. Ikoma

Existence of minimizers for some coupled nonlinear Schrödinger equations.

Springer INdAM Series Volume 2 (2013), 143-164.

2. N. Ikoma, A. Malchiodi and A. Mondino,

Area-constrained Willmore surfaces of small area in Riemannian three-manifolds:

an approach via Lyapunov-Schmidt reduction.

RIMS Kokyuroku Bessatsu B63 (2017), 31-50.

Proceeding (Without Peer-Review)

4. N. Ikoma

Kirchhoff 型方程式に対する特異摂動問題.

Surikaisekikenkyusho Kokyuroku, No. 1979 (2015), 89-106.

3. N. Ikoma

Some properties of eigenvalues for fully nonlinear operators.

Surikaisekikenkyusho Kokyuroku, No. 1959 (2015), 128-141.

2. N. Ikoma

Existence of eigenvalues and eigenfunctions for radially symmetric fully nonlinear elliptic operators.

Surikaisekikenkyusho Kokyuroku, No. 1845 (2013), 84-106.

1. N. Ikoma

A singular perturbation problem for coupled nonlinear Schroedinger equations.

Surikaisekikenkyusho Kokyuroku, No. 1671 (2009), 1-19.

Preprint 

1. J. Byeon, N. Ikoma, A. Malchiodi and L. Mari

Compactness via monotonicity in nonsmooth critical point theory, with application to Born-Infeld type equations. 

arXiv:2406.14853 [math.AP].