THEME01-3-1030-99/2008

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01-3-1030-99/2008

Priority:

Status:

In-progress

Theory of Condensed Matter

Leader:	V.B. Priezzhev
Scientific leader:	N.M. Plakida

Scientific Programme:
Multiparticle models of solids taking into consideration strong electron correlations, electron-lattice, and spin interactions to describe spectra of quasiparticle excitations, phase transitions and kinetic phenomena in solids. In equilibrium and nonequilibrium media with strong correlations such as liquids and nuclear matter, the processes of multifragmentation, clusterization in phase transitions and the influence of surface effects on properties of clusters. In the theory of superconductivity, nonstandard mechanisms of pairing in metal-oxides, the problem of bipolaron stability in a polaron gas environment, the influence of strong electric fields and temperature gradients on elastic, magnetic, and thermal properties of granular superconductors. For a study of mechanisms of phase transitions caused by charge, orbital, and magnetic ordering in magnetic semiconductors and in metals with a large magnetoresistance, experimental data obtained at the Frank Laboratory of Neutron Physics, JINR, by neutron scattering and the µSR method will be used.
Nonlinear problems in multiparticle theory will be studied by using modern methods of the renormalization group theory, the inverse scattering problem, fractal geometry, and the conformal field theory. The main subjects of the study are integrable systems, equilibrium systems of the statistical mechanics, and dissipative systems far from the thermodynamic equilibrium. The aim of these investigations is to reveal common properties of the multiparticle systems associated with the ideas of self-similarity and universality.
The microstructure of amorphous state will be studied in the framework of the theoretical model where topological disorder is introduced via arrays of disclination dipoles and loops. The thermal properties of disclinated media are of primary interest. The electronic spectrum of carbon materials, fullerenes and nanotubes, will be examined within the field-theory model adapted to account for nontrivial geometry of these nanostructures. The model of random Josephson junction arrays will be studied and applied to describe high-temperature granular superconductors.
In the theory of finite quantum systems, local and low-dimensional states of matter obtained in modern experiments will be investigated. In particular, properties of quasiparticles in mesoscopic systems and the Bose-Einstein condensation in atomic traps will be studied.

Expected main results in 2007:

Calculation of superconducting temperature in the copper-oxide compounds in the strong-coupling limit. Calculation of spectral functions of localized electrons within the diagram theory for the single-site Anderson model. Development of a theory of transport coefficients in solids based on the nonequilibrium statistical operator method. Revealing of effects of spin blockade on electronic transport in cobalt-oxides.

Calculation of the low-energy electronic spectrum of spheroidal fullerenes in a uniform magnetic field. Calculation of field emission characteristics of carbon ribbons. Study of quantum anomalies in spin systems. Evaluation of the phase-dismatching effect of electrons due to charged linear defects in semiconductors.
New results for the current fluctuations and the entropy production in the one-dimensional stochastic exclusion processes.

Development of a theory of Bose systems in random potentials with an arbitrarily strong disorder.

Calculations of the dispersion law for polaron in quantum wires, thin films, and bulk samples.

Investigation of the time evolution of an outgoing quantum state from a high-quality cavity with an absorbing coupling mirror in dependence on the ratio of the cavity absorption losses to the transmission ones.

List of Activities
	Activity or Experiment	Leader	Principal researchers
1.	Physical properties of complex materials and nanostructures	N.M. Plakida V.A. Osipov G. Repke
			W. Kleinig E.A. Kochetov S.E. Krasavin A.L. Kuzemsky V.A. Moskalenko V.S. Oudovenko N.B. Perkins J. Schmelzer S.A. Sergeenkov V.S. Shakhmatov V.Yu. Yushankhai
2.	Mathematical problems of many-particle systems	V.B. Priezzhev M.A. Smondyrev V.I. Yukalov
			L. Aleksandrov E.V. Bukina A.Yu. Cherny A.V. Chizhov V.M. Dubovik V.I. Inozemtsev A.E. Patrik A.M. Povolotsky V.N. Plechko K.V. Rerikh A.A. Shanenko V.P. Spiridonov P.E. Zhidkov

Collaboration
Country or international organization	City	Institute or Laboratory
Armenia	Yerevan	YerPhI
Belarus	Minsk	IMAP NASB
		IP NASB
		BGPU
Belgium	Antwerp	UA
Brazil	Brasilia, DF	UnB
	San Paulo, SP	USP
Bulgaria	Sofia	ISSP BAS
		SU
Canada	Montreal	Concordia
Czech Republic	Rez	NPI ASCR
France	Marseille	CPT
	Nice	UNSA
Germany	Bremen	Univ.
	Brunswick	TU
	Dortmund	Univ.
	Dresden	TUD
		IFW
	Duisburg	Univ.
	Leipzig	Univ.
	Magdeburg	OvGU
	Rostock	Univ.
	Stuttgart	MPI-FKF
Hungary	Budapest	KFKI RMKI
ICTP	Trieste
India	Mumbai	TIFR
Ireland	Dublin	DIAS
Italy	Catania	Univ.
	Salerno	Univ.
JINR	Dubna	FLNP
		LIT
Poland	Cracow	JU
	Poznan	IP AMU
Romania	Bucharest	IFIN-HH
Russia	Moscow	IGIC RAS
		LPI RAS
		MEPhI
		PFUR
		SMI RAS
		SINP MSU
		RRC KI
	Irkutsk	ISU
	Perm	PSU
	St. Petersburg	PDMI
	Troitsk	HPPI RAS
	Voronezh	VSU
	Yekaterinburg	IMP UB RAS
Montenegro	Podgorica	Univ.
Slovak Republic	Bratislava	IP SAS
	Kosice	IEP SAS
Slovenia	Ljubljana	UL
Switzerland	Villigen	PSI
Taiwan	Taipei	IP ASN
Ukraine	Kharkov	KFTI NASU
USA	New York, NY	CUNY
	Rochester, NY	UR
Uzbekistan	Tashkent	Assoc."P.-S." PTI
Vietnam	Hanoi	IP NCST

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