Dispersive collective charge modes in an incommensurately modulated cuprate Mott insulator

Wray, L. Andrew; Qian, Dong; Hsieh, David; Xia, Y.; Eisaki, H.; Hasan, M. Zahid

doi:10.1103/physrevb.76.100507

Cited by 10 publications

(9 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1(a)); however, it has been established in recent literature [4,5] that only the ladder sublattice contributes strongly to the low energy ð1:5 eVoEo4:5 eVÞ RIXS signal. The ladder is composed of corner sharing Cu-O plaquettes, as shown in Fig.…”

Section: Introductionmentioning

confidence: 98%

“…1(a). Spectral weight across the Mott gap from the other planar substructure, a chain of edge sharing plaquettes, is likely suppressed due to the small ratio of intersite hopping integral to the single band Hubbard model U parameter [4,6]. For this reason, we present spectra in units of momentum transfer (Q) defined by the reciprocal space of the ladder sublattice (p=c L , c L $3:9Å [7]).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Intermediate dimensional character of charge transfer excitation modes in a two-leg cuprate ladder

Wray

Qian

Hsieh

et al. 2008

Journal of Physics and Chemistry of Solids

Self Cite

View full text Add to dashboard Cite

Section: Introductionmentioning

confidence: 98%

Section: Introductionmentioning

confidence: 99%

Intermediate dimensional character of charge transfer excitation modes in a two-leg cuprate ladder

Wray

Qian

Hsieh

et al. 2008

Journal of Physics and Chemistry of Solids

Self Cite

View full text Add to dashboard Cite

“…Resonant inelastic x-ray scattering (RIXS) in hard xray regime, a recently developed experimental probe, have revealed various types of charge excitations in the strongly correlated electron systems, such as the charge excitation across the charge transfer (CT) gap [15,16,17,18], intraband excitations [18], molecular orbital excitations [19], d − d excitations [17], collective charge excitations [20], and even magnons [21]. The major advantage of RIXS is the possibility of studying charge excitations as a function of the momentum transfer q.…”

mentioning

confidence: 99%

Charge Excitations in the Stripe-OrderedLa5/3Sr1/3NiO4andLa

et al. 2009

View full text Add to dashboard Cite

Charge excitations were studied for stipe-ordered 214 compounds, La 5/3 Sr 1/3 NiO4 and 1/8-doped La2(Ba, Sr)xCuO4 using resonant inelastic x-ray scattering in hard x-ray regime. We have observed charge excitations at the energy transfer of ∼ 1 eV with the momentum transfer corresponding to the charge stripe spatial period both for the diagonal (nikelate) and parallel (cuprates) stripes. These new excitations can be interpreted as a collective stripe excitation or charge excitonic mode to a stripe-related in-gap state.There is accumulation of theoretical and experimental implications that the inhomogeneous charge state, such as a charge stripe state, occurring as a result of the carrier doping into the strongly correlated electron system is intimately related to the realization of high temperature superconductivity in cuprates [1,2]. Understanding the dynamics of the charge stripe state is one of the basic problems. To date, whereas the dynamics in spin sector has been studied extensively by neutron scattering [3,4,5,6], the dynamics in charge sector is yet to be understood.The 214 type nickelates and cuprates, family compounds of the firstly discovered high temperature superconductor La 2−x Ba x CuO 4 , exhibit charge stripe order when holes are doped. The stripe order has been comprehensively studied by diffraction techniques [7,8,9,10] and characterized by antiphase antiferromagnetic domains divided by one dimensional charge stripes where doped holes are confined. Upon carrier doping, La 2−x Sr x NiO 4 (LSNO) shows ordered state of "diagonal" stripes, where the charge stripes run along the diagonal direction of the NiO 2 square lattice [7] (Fig. 1 a). Holedoped 214 cuprates La 2−x (Ba, or Sr) x CuO 4 (LBCO or LSCO) show diagonal stripe order in the low doping insulating region [11], whereas in the superconducting dome the systems, particularly LBCO, show static order of "parallel" stripes only in the vicinity of x = 0.125 [12,13] where the superconductivity is suppressed [14]. This is frequently quoted as 1/8 anomaly. Here the charge stripes are parallel to the Cu-O-Cu bond (Fig. 1 b). Consequently, relation between the dynamical fluctuation of parallel stripes and the superconductivity is of interest.Resonant inelastic x-ray scattering (RIXS) in hard xray regime, a recently developed experimental probe, have revealed various types of charge excitations in the strongly correlated electron systems, such as the charge RIXS is an ideal probe for detecting charge excitations associated with the stripe having a specific momentum

show abstract

“…143,144) A RIXS experiment at the Cu K-edge on Sr 14 Cu 24 O 41 was performed by three groups independently. 129,145,146) A dispersive excitation observed around 2-4 eV is attributed to the Mott gap excitation of the ladder part, which is proved by the periodicity of the momentum dependence. The Mott gap excitation shifts to a higher energy with the momentum along the ladder.…”

Section: )mentioning

confidence: 90%

“…Two materials, SrCuO 2 and Sr 2 CuO 3 , were studied by Cu K-edge RIXS, and the momentum dependence of their Mott gap excitation was measured. [122][123][124][125][126][127][128][129] The other is the edge-sharing chain where neighboring CuO 4 plaquettes share their edge. The bond angle of Cu-O-Cu of the edge-sharing chain is close to 90 in contrast to that of the two-dimensional CuO 2 square lattice and corner-sharing chain.…”

Section: Cupratesmentioning

confidence: 99%

Inelastic X-ray Scattering Studies of Electronic Excitations

2013

View full text Add to dashboard Cite

Inelastic x-ray scattering (IXS) has developed into one of the most powerful momentum-resolved spectroscopies. Especially in the last decade, it has achieved significant progress utilizing brilliant x-rays from third-generation synchrotron radiation facilities. Simultaneously, theoretical efforts have been made to predict or interpret the experimental spectra. One of the scientific fields studied intensively by IXS is strongly correlated electron systems, where the interplay of charge, spin, and orbital degrees of freedom determines their physical properties. IXS can provide a new insight into the electron dynamics of the systems through the observation of charge, spin, and orbital excitations. Focusing on the momentum-resolved electronic excitations in strongly correlated electron systems, we review IXS studies and the present capabilities of IXS for the study of the dynamics of materials. With nonresonant inelastic x-ray scattering (NIXS), one can directly obtain dynamical charge correlation and we discuss its complementary aspects with inelastic neutron scattering. NIXS also has a unique capability of measuring higher multipole transitions, which are usually forbidden in conventional optical absorption. Resonant inelastic x-ray scattering (RIXS) is now established as a valuable tool for measuring charge, spin, and orbital excitations in a momentum-resolved manner. We describe RIXS works on cuprates in detail and show what kind of electronic excitations have been observed. We also discuss RIXS studies on other transition-metal compounds. Finally, we conclude with an outlook on IXS using next-generation x-ray sources.

show abstract

Dispersive collective charge modes in an incommensurately modulated cuprate Mott insulator

Cited by 10 publications

References 23 publications

Intermediate dimensional character of charge transfer excitation modes in a two-leg cuprate ladder

Intermediate dimensional character of charge transfer excitation modes in a two-leg cuprate ladder

Charge Excitations in the Stripe-OrderedLa5/3Sr1/3NiO4andLa

Inelastic X-ray Scattering Studies of Electronic Excitations

Contact Info

Product

Resources

About