Theoretical study of the spin and charge dynamics of two-leg ladders as probed by resonant inelastic x-ray scattering

Kumar, Umesh; Nocera, Alberto; Dagotto, Elbio; Johnston, Steven

doi:10.1103/physrevb.99.205130

Cited by 20 publications

(44 citation statements)

References 78 publications

(175 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our results for I s1 (q, ω) as well as I s2 (q, ω) agree well with the findings of Ref. 45 in the undoped case for the strong-rung limit in the NSC channel. Based on our bond operator representation formulation calculation we find an additional finite signal at zero momentum transfer.…”

Section: Spin Laddersupporting

confidence: 91%

“…In Figs. 11(a) and 11(d) we show the results of the one-triplon intensity I s1 (q, ω), in 11(b) and 11(e) we plot the two-triplon intensity I s2 (q, ω), and in the last column we show the total two-triplon contribution I total the weaker rung coupling limit produces a more intense RIXS signal [45].…”

Section: Spin Laddermentioning

confidence: 99%

“…Resonant inelastic x-ray scattering can detect selection rule allowed triplon excitations with ∆S = 0, 1, 2, where ∆S refers to spin angular momentum change. In fact, experimental and theoretical RIXS efforts related to the study of triplon excitation for two-leg spin ladder have been reported in the literature [43][44][45]. The experimental study found two-triplon excitation signal in the spin ladder [33].…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

K -edge and L3 -edge RIXS study of columnar and staggered quantum dimer phases of the square lattice Heisenberg model

He¹,

Datta²,

Yao³

2020

Phys. Rev. B

View full text Add to dashboard Cite

We compute the K and L 3 -edge resonant inelastic x-ray scattering (RIXS) spectrum of the columnar and the staggered quantum dimer states accessible to the square lattice Heisenberg magnet. Utilizing a bond operator representation mean field theory we investigate the RIXS features of the one-and two-triplon excitation spectrum supported by the quantum dimer model in the background of condensed singlet excitation. We find that the two-triplon excitation boundary lies within a 124 (78) meV to 414 (345) meV energy range for the columnar (staggered) phase. We estimated the two-triplon gap to be 124 (78) meV for the columnar (staggered) dimer phase. The highest intensity of the K -edge RIXS spectrum is centralized approximately around the (π/2, π/2) point for both the columnar and the staggered phases. At the L 3 -edge we study the one-and two-triplon signal considering experimental scattering geometry, polarization restriction, and experimental resolution effects. Our calculations find an additional contribution to the two-triplon RIXS signal, not previously reported in the literature, that originates from the local hard-core dimer constraint. This leads to a finite non-zero signal at the (0,0) momentum transfer which can offer an explanation for the existing ladder RIXS experiments and also predicts a non-zero signal for the two-dimensional quantum dimer system. We find that the L 3 edge RIXS response of the one-and two-triplon signal could exist in antiphase rung modulation for zero and π as found in inelastic neutron scattering. We also consider static crystal twinning at the L 3 -edge RIXS signal to mimic realistic crystal effects. Since the disordered phase has the potential to harbor a variety of quantum paramagnetic states, our RIXS calculations provide useful signatures to identify the true nature of the ordering pattern. PACS number(s): 78.70. Ck, 75.10.Jm

show abstract

Section: Spin Laddersupporting

confidence: 91%

Section: Spin Laddermentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

K -edge and L3 -edge RIXS study of columnar and staggered quantum dimer phases of the square lattice Heisenberg model

He¹,

Datta²,

Yao³

2020

Phys. Rev. B

View full text Add to dashboard Cite

show abstract

“…In the case of spin-ladders, three-triplon bound states were predicted in the same channel [33] using the continuous unitary transformation method. However, the extent to which higher-order corrections to the UCL expansion are required for the NSC excitations at L-edges [9,34,35] has not been widely studied.…”

mentioning

confidence: 99%

“…While the KH formalism captures the spectral weight distribution of both the two-and four-spinon excitations, it is desirable to identify the correlation functions leading to these excitations using the UCL expansion [9,23,35]. For a half-filled antiferromagnetic d 9 cuprate, the zerothorder term in the expansion of the SC and NSC channels are elastic scattering and the conventional dynamical spin structure factor S(q, ω), respectively [9,34,44]. Corrections to these terms are provided by the higher-order terms in the UCL expansion.…”

mentioning

confidence: 99%

Unraveling higher-order corrections in the spin dynamics of RIXS spectra

Kumar,

Nag,

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

Resonant inelastic x-ray scattering (RIXS) is an evolving tool for investigating spin dynamics of strongly correlated materials, which complements inelastic neutron scattering. Both techniques have found that non-spin-conserving (NSC) excitations in quasi-1D isotropic quantum antiferromagnets are confined to the two-spinon phase space. Outside this phase space, only spin-conserving (SC) four-spinon excitations have been detected using O K-edge RIXS. Here, we investigate SrCuO2 and find four-spinon excitations outside the two-spinon phase space at both O K-and Cu L3-edges. Using the Kramers-Heisenberg formalism, we demonstrate that the four-spinon excitations arise from both SC and NSC processes at Cu L3-edge. We show that these new excitations only appear in the second-order terms of the ultra-fast core-hole lifetime expansion and arise from long-range spin fluctuations. These results thus open a new window to the spin dynamics of quantum magnets.

show abstract

Emergence of superconductivity in doped multiorbital Hubbard chains

et al. 2020

View full text Add to dashboard Cite

We introduce a variational state for one-dimensional two-orbital Hubbard models that intuitively explains the recent computational discovery of pairing in these systems when hole doped. Our ansatz is an optimized linear superposition of Affleck–Kennedy–Lieb–Tasaki valence-bond states, rendering the combination a valence-bond liquid dubbed orbital resonant valence bond. We show that the undoped (one-electron/orbital) quantum state of two sites coupled into a global spin singlet is exactly written employing only spin-1/2 singlets linking orbitals at nearest-neighbor sites. Generalizing to longer chains defines our variational state visualized geometrically expressing our chain as a two-leg ladder, with one orbital per leg. As in Anderson’s resonating valence-bond state, our undoped variational state contains preformed singlet pairs that via doping become mobile, leading to superconductivity. Doped real materials with one-dimensional substructures, two near-degenerate orbitals, and intermediate Hubbard U/W strengths—W the carrier’s bandwidth—could realize spin-singlet pairing if on-site anisotropies are small. If these anisotropies are robust, spin-triplet pairing emerges.

show abstract

Theoretical study of the spin and charge dynamics of two-leg ladders as probed by resonant inelastic x-ray scattering

Cited by 20 publications

References 78 publications

K -edge and L3 -edge RIXS study of columnar and staggered quantum dimer phases of the square lattice Heisenberg model

K -edge and L3 -edge RIXS study of columnar and staggered quantum dimer phases of the square lattice Heisenberg model

Unraveling higher-order corrections in the spin dynamics of RIXS spectra

Emergence of superconductivity in doped multiorbital Hubbard chains

Contact Info

Product

Resources

About