Resonances and Spectral Shift Function near the Landau levels
[Résonances et fonction de décalage spectral près des niveaux de Landau]
Bony, Jean-François ; Bruneau, Vincent ; Raikov, Georgi
Annales de l'Institut Fourier, Tome 57 (2007), p. 629-671 / Harvested from Numdam

On étudie l’opérateur de Schrödinger magnétique en dimension 3, H=H 0 +VH 0 =(-i-A) 2 -b, A est un potentiel magnétique générant un champ magnétique constant de force b>0 fixée et V est un potentiel électrique qui décroît super-exponentiellement dans la direction du champ magnétique. On montre que la résolvante de H admet un prolongement méromorphe du plan supérieur une certaine surface de Riemann et on définit les résonances de H comme les pôles de cette extension méromorphe. On étudie leur répartition près d’un niveau de Landau fixé 2bq, q. On obtient d’abord des majorations du nombre de résonances dans des petits domaines proches de 2bq. Sous des hypothses supplémentaires, on prouve des minorations du nombre de résonances qui implique la présence d’une infinité de résonances ou bien l’absence de résonances dans certains secteurs de sommet 2bq. Finalement, on montre que la fonction de décalage spectral (FDS) associée à la paire (H,H 0 ) est la somme de mesures harmoniques associées aux résonances et de la partie imaginaire d’une fonction holomorphe. Cette formule justifie l’approximation de Breit-Wigner, implique une formule de trace à la Sjöstrand et donne des informations sur les singularités de la FDS aux niveaux de Landau.

We consider the 3D Schrödinger operator H=H 0 +V where H 0 =(-i-A) 2 -b, A is a magnetic potential generating a constant magneticfield of strength b>0, and V is a short-range electric potential which decays superexponentially with respect to the variable along the magnetic field. We show that the resolvent of H admits a meromorphic extension from the upper half plane to an appropriate Riemann surface , and define the resonances of H as the poles of this meromorphic extension. We study their distribution near any fixed Landau level 2bq, q. First, we obtain a sharp upper bound of the number of resonances in a vicinity of 2bq. Moreover, under appropriate hypotheses, we establish corresponding lower bounds which imply the existence of an infinite number of resonances, or the absence of resonances in certain sectors adjoining 2bq. Finally, we deduce a representation of the derivative of the spectral shift function (SSF) for the operator pair (H,H 0 ) as a sum of a harmonic measure related to the resonances, and the imaginary part of a holomorphic function. This representation justifies the Breit-Wigner approximation, implies a trace formula, and provides information on the singularities of the SSF at the Landau levels.

Publié le : 2007-01-01
DOI : https://doi.org/10.5802/aif.2270
Classification:  35P25,  35J10,  47F05,  81Q10
@article{AIF_2007__57_2_629_0,
     author = {Bony, Jean-Fran\c cois and Bruneau, Vincent and Raikov, Georgi},
     title = {Resonances and Spectral Shift Function near the Landau levels},
     journal = {Annales de l'Institut Fourier},
     volume = {57},
     year = {2007},
     pages = {629-671},
     doi = {10.5802/aif.2270},
     zbl = {1129.35053},
     mrnumber = {2310953},
     language = {en},
     url = {http://dml.mathdoc.fr/item/AIF_2007__57_2_629_0}
}
Bony, Jean-François; Bruneau, Vincent; Raikov, Georgi. Resonances and Spectral Shift Function near the Landau levels. Annales de l'Institut Fourier, Tome 57 (2007) pp. 629-671. doi : 10.5802/aif.2270. http://gdmltest.u-ga.fr/item/AIF_2007__57_2_629_0/

[1] Avron, J.; Herbst, I.; Simon, B. Schrödinger operators with magnetic fields. I. General interactions, Duke Math. J., Tome 45 (1978), pp. 847-883 | Article | MR 518109 | Zbl 0399.35029

[2] Barreto, A. Sá; Zworski, M. Existence of resonances in three dimensions, Commun. Math. Phys., Tome 173 (1995), pp. 401-415 | Article | MR 1355631 | Zbl 0835.35099

[3] Bony, J.-F.; Sjöstrand, J. Trace formula for resonances in small domains, J. Funct. Anal., Tome 184 (2001), pp. 402-418 | Article | MR 1851003 | Zbl 1068.47055

[4] Bouclet, J. M. Traces formulae for relatively Hilbert-Schmidt perturbations, Asymptot. Anal., Tome 32 (2002), pp. 257-291 | MR 1993651 | Zbl 1062.47021

[5] Bouclet, J. M. Spectral distributions for long range perturbations, J. Funct. Anal., Tome 212 (2004), pp. 431-471 | Article | MR 2064934 | Zbl 02105600

[6] Bruneau, V.; Petkov, V. Meromorphic continuation of the spectral shift function, Duke Math. J., Tome 116 (2003), pp. 389-430 | Article | MR 1958093 | Zbl 1033.35081

[7] Bruneau, V.; Pushnitski, A.; Raikov, G. D. Spectral shift function in strong magnetic fields, Algebra i Analysis, Tome 16 (2004), pp. 207-238 (English transl.: St. Petersburg Math. J. 16 (2005), p.181-209) | MR 2069004 | Zbl 1082.35115

[8] Delande, D.; Bommier, A.; Gay, J.-C. Positive-Energy spectrum of the hydrogen atom in a magnetic field, Phys. Rev. Lett., Tome 66 (1991), pp. 141-144 | Article

[9] Dimassi, M.; Sjöstrand, J. Spectral asymptotics in the semi-classical limit, Lecture Notes Series, London Math. Society, Cambridge University Press, Tome 268 (1999) | MR 1735654 | Zbl 0926.35002

[10] Dimassi, M.; Zerzeri, M. A local trace formula for resonances of perturbed periodic Schrödinger operators, J. Funct. Anal., Tome 198 (2003), pp. 142-159 | Article | MR 1962356 | Zbl 01901766

[11] Fernández, C.; Raikov, G. D. On the singularities of the magnetic spectral shift function at the Landau levels, Ann. Henri Poincaré, Tome 5 (2004), pp. 381-403 | Article | MR 2057679 | Zbl 1062.81043

[12] Filonov, N.; Pushnitski, A. Spectral asymptotics of Pauli operators and orthogonal polynomials in complex domains, Commun. Math. Phys., Tome 264 (2006), pp. 759-772 | Article | MR 2217290 | Zbl 1106.81040

[13] Froese, R. Asymptotic distribution of resonances in one dimension, J. Diff. Equa., Tome 137 (1997), pp. 251-272 | Article | MR 1456597 | Zbl 0955.35057

[14] Froese, R.; Waxler, R. Ground state resonances of a hydrogen atom in an intense magnetic field, Rev. Math. Phys., Tome 7 (1995), pp. 311-361 | Article | MR 1326138 | Zbl 0836.47048

[15] Fulton, W. Algebraic Topology, A First Course, Graduate Texts in Mathematics, Springer (1995) | MR 1343250 | Zbl 0852.55001

[16] Gohberg, I. C.; Krein, M. G. Introduction to the theory of linear nonselfadjoint operators, Translations of Mathematical Monographs, American Math. Society, Providence, R.I., Tome 18 (1969) | MR 246142 | Zbl 0181.13504

[17] Koplienko, L. S. Trace formula for non trace-class perturbations, Sibirsk. Mat. Zh., Tome 25 (1984), pp. 62-71 (English transl.: Siberian Math. J. 25 (1984), p.735-743) | MR 762239 | Zbl 0574.47021

[18] Koplienko, L. S. Regularized function of spectral shift for a one-dimensional Schrödinger operator with slowly decreasing potential, Sibirsk. Mat. Zh., Tome 26 (1985), p. 72-77, 62-71 (English transl.: Siberian Math. J. 26 (1985), p.365–369) | MR 792056 | Zbl 0581.47034

[19] Krein, M. G. On perturbation determinants and a trace formula for unitary and self-adjoint operators, Dokl. Akad. Nauk SSSR, Tome 144 (1962), pp. 268-271 | MR 139006 | Zbl 0191.15201

[20] Landau, L. Diamagnetismus der Metalle, Z. Physik, Tome 64 (1930), pp. 629-637 | Article

[21] Petkov, V.; Zworski, M. Semi-classical estimates on the scattering determinant, Ann. H. Poincaré, Tome 2 (2001), pp. 675-711 | Article | MR 1852923 | Zbl 1041.81041

[22] Raikov, G. D. Eigenvalue asymptotics for the Schrödinger operator with homogeneous magnetic potential and decreasing electric potential. I. Behaviour near the essential spectrum tips, Commun. PDE, Tome 15 (1990), pp. 407-434 (Errata: Commun. PDE 18 (1993), 1977–1979) | Article | MR 1044429 | Zbl 0739.35055

[23] Raikov, G. D. Spectral shift function for Schrödinger operators in constant magnetic fields, Cubo, Tome 7 (2005), pp. 171-199 | MR 2186031 | Zbl 1103.81018

[24] Raikov, G. D. Spectral shift function for magnetic Schrödinger operators, Mathematical Physics of Quantum Mechanics, Proceedings of the Conference Math. 9, Giens (France), 2004, Lecture Notes in Physics, Springer, Tome 690 (2006), pp. 451-465 | MR 2235707 | Zbl 1167.81383

[25] Raikov, G. D.; Warzel, S. Quasi-classical versus non-classical spectral asymptotics for magnetic Schödinger operators with decreasing electric potentials, Rev. Math. Phys., Tome 14 (2002), pp. 1051-1072 | Article | MR 1939760 | Zbl 1033.81038

[26] Sjöstrand, J. Lectures on resonances (Preprint, www.math.polytechnique.fr/~sjoestrand/)

[27] Sjöstrand, J. A trace formula for resonances and application to semi-classical Schrödinger operator, Séminaire EDP, Exposé II, École Polytechnique (1996-1997), pp. 1-17 | Numdam | MR 1482808 | Zbl 1061.35506

[28] Sjöstrand, J. A trace formula and review of some estimates for resonances, Microlocal analysis and spectral theory (Lucca, 1996), p.377–437, NATO Adv. Sci. Inst. Ser. C Math. Phys. Sci., Dordrecht, Kluwer Acad. Publ., Tome 490 (1997) | MR 1451399 | Zbl 0877.35090

[29] Sjöstrand, J. Resonances for bottles and trace formulae, Math. Nachr., Tome 221 (2001), pp. 95-149 | Article | MR 1806367 | Zbl 0979.35109

[30] Sobolev, A. V. Asymptotic behavior of energy levels of a quantum particle in a homogeneous magnetic field perturbed by an attenuating electric field. II, Probl. Mat. Fiz., Leningrad. Univ., Tome 11 (1986), pp. 232-248 | MR 857118

[31] Wang, X. P. Barrier resonances in strong magnetic fields, Commun. Partial Differ. Equations, Tome 17 (1992), pp. 1539-1566 | Article | MR 1187621 | Zbl 0795.35097