Small polarons and magnetic antiphase boundaries in Ca2-xNaxCuO2Cl2 (x=0.06, 0.12):: Origin of striped phases in cuprates

被引:17
作者
Patterson, C. H. [1 ]
机构
[1] Univ Dublin Trinity Coll, Sch Phys, Dublin 2, Ireland
关键词
D O I
10.1103/PhysRevB.77.094523
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
We report hybrid density functional theory calculations on hole doped Ca2-xNaxCuO2Cl2 performed in 4 x 4, 4 root 2 x 4 root 2, and 8 x 2 supercells with hole concentrations x=0.0625 and x=0.125. Holes at the lower concentration form small polarons, in which the hole is mainly localized on four oxygen ions surrounding one copper ion. The polaron is a spin one-half ferromagnetic polaron (Cu5O4), in which the moment on the central copper ion is parallel to those on the four neighboring copper ions and the moment on the oxygen ions is opposed to that on the copper ions. This is therefore an Emery-Reiter spin polaron rather than a Zhang-Rice singlet. At the higher hole concentration (x=0.125), many cuprates form stripes. Hybrid density functional theory calculations on linear chains of spin polarons separated by 4a(0) show a group of bands localized mainly on the stripe. Spins on neighboring copper ions in the stripe are parallel and so the stripe forms a magnetic antiphase boundary between antiferromagnetically ordered blocks of copper spins. Stripes of this kind, which run in one direction only, may explain recent scanning tunneling microscopy data from Ca2-xNaxCuO2Cl2 by Kohsaka et al. [Science 315, 1380 (2007)]. We also consider an ordered spin polaron phase where magnetic antiphase boundaries intersect at right angles. In this case, sets of four copper ions in squares at stripe intersections have parallel spins. This phase may be the 4 x 4 checkerboard pattern reported by Hanaguri et al. [Nature (London) 430, 1001 (2004)].
引用
收藏
页数:11
相关论文
共 79 条
[1]   Spatially modulated 'Mottness' in La2-xBaxCuO4 [J].
Abbamonte, P ;
Rusydi, A ;
Smadici, S ;
Gu, GD ;
Sawatzky, GA ;
Feng, DL .
NATURE PHYSICS, 2005, 1 (03) :155-158
[2]   Computation of stripes in cuprates within the LDA+U method -: art. no. 172501 [J].
Anisimov, VI ;
Korotin, MA ;
Mylnikova, AS ;
Kozhevnikov, AV ;
Korotin, DM ;
Lorenzana, J .
PHYSICAL REVIEW B, 2004, 70 (17) :1-4
[3]   ON THE STRUCTURAL-PROPERTIES OF NACL - AN ABINITIO STUDY OF THE B1-B2 PHASE-TRANSITION [J].
APRA, E ;
CAUSA, M ;
PRENCIPE, M ;
DOVESI, R ;
SAUNDERS, VR .
JOURNAL OF PHYSICS-CONDENSED MATTER, 1993, 5 (18) :2969-2976
[4]   DENSITY-FUNCTIONAL THERMOCHEMISTRY .3. THE ROLE OF EXACT EXCHANGE [J].
BECKE, AD .
JOURNAL OF CHEMICAL PHYSICS, 1993, 98 (07) :5648-5652
[5]   DENSITY-FUNCTIONAL EXCHANGE-ENERGY APPROXIMATION WITH CORRECT ASYMPTOTIC-BEHAVIOR [J].
BECKE, AD .
PHYSICAL REVIEW A, 1988, 38 (06) :3098-3100
[6]   POLARON CONTRIBUTION TO THE INFRARED OPTICAL-RESPONSE OF LA2-XSRXCUO4+DELTA AND LA2-XSRXNIO4+DELTA [J].
BI, XX ;
EKLUND, PC .
PHYSICAL REVIEW LETTERS, 1993, 70 (17) :2625-2628
[7]   OUT-OF-PLANE ORBITAL CHARACTERS OF INTRINSIC AND DOPED HOLES IN LA2-XSRXCUO4 [J].
CHEN, CT ;
TJENG, LH ;
KWO, J ;
KAO, HL ;
RUDOLF, P ;
SETTE, F ;
FLEMING, RM .
PHYSICAL REVIEW LETTERS, 1992, 68 (16) :2543-2546
[8]   FREQUENCY AND MAGNETIC-FIELD DEPENDENCE OF THE DIELECTRIC-CONSTANT AND CONDUCTIVITY OF LA2CUO4+Y [J].
CHEN, CY ;
BIRGENEAU, RJ ;
KASTNER, MA ;
PREYER, NW ;
THIO, T .
PHYSICAL REVIEW B, 1991, 43 (01) :392-401
[9]   FREQUENCY-DEPENDENCE OF THE CONDUCTIVITY AND DIELECTRIC-CONSTANT OF LA2CUO4+Y NEAR THE INSULATOR-METAL TRANSITION [J].
CHEN, CY ;
PREYER, NW ;
PICONE, PJ ;
KASTNER, MA ;
JENSSEN, HP ;
GABBE, DR ;
CASSANHO, A ;
BIRGENEAU, RJ .
PHYSICAL REVIEW LETTERS, 1989, 63 (20) :2307-2310
[10]   Spin waves and electronic interactions in La2CuO4 [J].
Coldea, R ;
Hayden, SM ;
Aeppli, G ;
Perring, TG ;
Frost, CD ;
Mason, TE ;
Cheong, SW ;
Fisk, Z .
PHYSICAL REVIEW LETTERS, 2001, 86 (23) :5377-5380