270 likes | 376 Vues
Unusual magnetotransport properties of NbSe 3 single crystals at low temperature. A.A.Sinchenko MEPhI, Moscow, Russia Yu.I.Latyshev, A.P.Orlov IRE RAS, Moscow, Russia P.Monceau CRTBT-CNRS Grenoble, France. Outline. Magnetoresistance of NbSe 3 : history In-plain negative magnetoresistance
E N D
Unusual magnetotransport properties of NbSe3 single crystals at low temperature A.A.Sinchenko MEPhI, Moscow, Russia Yu.I.Latyshev, A.P.Orlov IRE RAS, Moscow, Russia P.Monceau CRTBT-CNRS Grenoble, France
Outline • Magnetoresistance of NbSe3: history • In-plain negative magnetoresistance • Quantum linear magnetoresistance • Phase of Shubnikov-de Haas oscillations at different field orientations • Summary
J.Richard, et al, PRB, 1987 R.M.Fleming, et al, PRB,1978 P.Monceau, et al, J.Phys.C, 1978 R.M.Fleming, et al, PRB, 1978 M.P.Everson, et al, PRB, 1985 R.V.Coleman, et al, PRL, 1985 J.Richard, et al, PRB, 1987 O.Laborde, et al, EPL, 1987 M.P.Everson, et al, PRB, 1987 P.Monceau, J.Richard, PRB, 1988 T.M.Tritt, et al, PRB, 1988, R.V.Coleman, et al, PRB, 1990 Solid line - function 0/(2sin2+cos2)1/2 =1/8
J.Richard, et al, PRB, 1987 R.M.Fleming, et al, PRB,1978 P.Monceau, et al, J.Phys.C, 1978 R.M.Fleming, et al, PRB, 1978 M.P.Everson, et al, PRB, 1985 R.V.Coleman, et al, PRL, 1985 J.Richard, et al, PRB, 1987 O.Laborde, et al, EPL, 1987 M.P.Everson, et al, PRB, 1987 P.Monceau, J.Richard, PRB, 1988 T.M.Tritt, et al, PRB, 1988, R.V.Coleman, et al, PRB, 1990 Solid line - function 0/(2sin2+cos2)1/2 =1/8
a* c Results B B b I I 5.3 m
a* c Results B B b I I 5.3 m 2.7m
a* a* c c Results Results B B B B b b I I I I 5.3 m 5.3 m 2.7m 1.3m
a* a* a* a* c c c c Results Results Results Results B B B B B B B B b b b b I I I I I I I I 5.3 m 5.3 m 5.3 m 5.3 m 2.7m 2.7m 1.3m 1.1m
a* a* a* a* a* c c c c c Results Results Results Results Results B B B B B B B B B b b b b b I I I I I I I I I 5.3 m 5.3 m 5.3 m 5.3 m 5.3 m 2.7m 2.7m 1.3m 1.1m
a* a* a* a* a* c c c c c Results Results Results Results Results B B B B B B B B B B b b b b b I I I I I I I I I I 5.3 m 5.3 m 5.3 m 5.3 m 5.3 m 2.7m 2.7m 1.3m 1.1m
Results Temperature evolution d=1 m
Results Bmax
Results Bmax Bmax is independent on d. At T=4.2 K Bmax=0.12 T.
Results Bmax Bmax is independent on d. At T=4.2 K Bmax=0.12 T. region of transition to quantum limit at B=0.31 T
Results Bmax Bmax is independent on d. At T=4.2 K Bmax=0.12 T. region of transition to quantum limit at B=0.31 T Sharp drop of resistance in transition region 0.1-0.4 T
Results Bmax Bmax is independent on d. At T=4.2 K Bmax=0.12 T. Bmin region of transition to quantum limit at B=0.31 T Sharp drop of resistance in transition region 0.1-0.4 T
Results Bmax Bmax is independent on d. At T=4.2 K Bmax=0.12 T. A=const Bmin Larmor diameter corresponding to Bmin Dd region of transition to quantum limit at B=0.31 T Sharp drop of resistance in transition region 0.1-0.4 T
Results Bmax Bmax is independent on d. At T=4.2 K Bmax=0.12 T. A=const Bmin Larmor diameter corresponding to Bmin Dd region of transition to quantum limit dc=5-8m at B=0.31 T Sharp drop of resistance in transition region 0.1-0.4 T
Results Bmax Bmax is independent on d. At T=4.2 K Bmax=0.12 T. A=const Bmin Larmor diameter corresponding to Bmin Dd region of transition to quantum limit dc=5-8m at B=0.31 T Sharp drop of resistance in transition region 0.1-0.4 T
Quantum lenear magnetoresistance [AA..Abrikosov, J.Phys.A (2003); PRB (1998), PRB (1999)] The conditions: In the case of small electron groups (layer materials with small electron and hole pockets) in strong (1) magnetic field perpendicular to the field resistivity: Landau bands in an isotropic model for moderate magnetic field. Many bands contain electrons NbSe3 1 at H=0.03 T Landau bands in the quantum limit. Only the lowest band contains electrons.
Below quantum limit, D>d R B2 B B B B B B B B B I I I I I I I I I Quantum limit, D>d negative magnetoresistance e Quntum limit, D<d Quantum linear magbetoresistance
Angle dependence of magnetoresistance B I I I I I I I I I
Angle dependence of magnetoresistance B I I I I I I I I I
Only parallel to c-axis component of magnetic field determines the orbital motion of carriers
Angle dependence of magnetoresistance (d>dc) B I I I I I I I I I axially symmetric case: momenta of pockets carriers are predominantly oriented along b-axis (chain direction) of crystal (Sinchenko, Latyshev, Monceau, 2005)
Summary • The negative in-plain magnetoresistance has been observed in NbSe3 single crystals with the sample thickness less some critical value that is determined by the Larmor diameter at magnetic field corresponding to transition to the quantum limit. • The momenta of carriers that are not condensed in CDW are predominantly oriented along the conducting chains.