Spin gap and dynamics in<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">Sr</mml:mi></mml:mrow><mml:mrow><mml:mn>14</mml:mn><mml:mi>−</mml:mi><mml:mi>x</mml:mi></mml:mrow></mml:msub></mml:mrow><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">Ca</mml:mi></mml:mrow><mml:mrow><mml:mi>x</mml:mi></mml:mrow></mml:msub></mml:mrow><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">Cu</mml:mi></mml:mrow><mml:mrow><

Magishi, Ko−ichi; Matsumoto, Shinji; Kitaoka, Y.; Ishida, K.; Asayama, Kunisuke; Uehara, M.; Nagata, Takashi; Akimitsu, Jun

doi:10.1103/physrevb.57.11533

Cited by 148 publications

(91 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The spin part of the NMR shift, which is directly proportional to the spin susceptibility, allows an accurate determination of these gaps. Upon Ca substitution, the amplitude of the spin gap in the ladders decreases from 500K [14,15] or 430K [16] for x = 0 down to 250K for x=12 [15,16] while it remains practically unchanged in the chains (125 − 140K) [14,16]. Therefore, the spin gapped structure survives the existence of a finite concentration of holes in the ladders in agreement with theoretical suggestions [13,17,18].…”

Section: Introductionsupporting

confidence: 67%

“…However, considering the 100 ppm change of the quadrupolar contribution at B = 9.3T ( b) which is observed upon Ca substitution between x = 0 and x = 11.5 in Sr 14−x Ca x Cu 24 O 41 [16,15] and the expected equivalence between the chemical pressure of Ca and the applied pressure which is a result of the present study we can conclude that a change of the quadrupolar term exceeding 100 ppm in 32kbar is very unlikely .…”

Section: Methodsmentioning

confidence: 73%

“…Following the determination of the quadrupole tensor in Sr 2.5 Ca 11.5 Cu 24 O 41 [15], the second term in Eq. (2) amounts to 42kHz (400ppm) with a negligible temperature dependence as compared to the temperature dependence of the first contribution since (ν c − ν a ) remains practically temperature independent [16].…”

Section: Methodsmentioning

confidence: 99%

See 2 more Smart Citations

( Sr / Ca ) 14 Cu 24 O 41 spin ladders studied by NMR under pressure

et al. 2001

View full text Add to dashboard Cite

63 Cu-NMR measurements have been performed on two-leg hole-doped spin ladders Sr14−xCaxCu24O41 single crystals 0 ≤ x ≤ 12 at several pressures up to the pressure domain where the stabilization of a superconducting ground state can be achieved. The data reveal a marked decrease of the spin gap derived from Knight shift measurements upon Ca substitution and also under pressure and confirm the onset of low lying spin excitations around Pc as previously reported. The spin gap in Sr2Ca12Cu24O41 is strongly reduced above 20kbar. However, the data of an experiment performed at P = 36kbar where superconductivity has been detected at 6.7K by an inductive technique have shown that a significant amount of spin excitations remains gapped at 80K when superconductivity sets in. The standard relaxation model with two and three-magnon modes explains fairly well the activated relaxation data in the intermediate temperature regime corresponding to gapped spin excitations using the spin gap data derived from Knight shift experiments.The data of Gaussian relaxation rates of heavily doped samples support the limitation of the coherence lenght at low temperature by the average distance between doped holes. We discuss the interplay between superconductivity and the spin gap and suggest that these new results support the exciting prospect of superconductivity induced by the interladder tunnelling of preformed pairs as long as the pressure remains lower than the pressure corresponding to the maximum of the superconducting critical temperature.

show abstract

Section: Introductionsupporting

confidence: 67%

Section: Methodsmentioning

confidence: 73%

See 1 more Smart Citation

( Sr / Ca ) 14 Cu 24 O 41 spin ladders studied by NMR under pressure

et al. 2001

View full text Add to dashboard Cite

show abstract

“…Previous NMR studies on Sr 14 Cu 24 0 41 have provided clear evidence for the formation of gaps for low-lying spin excitations in both the chain and the ladder sites [7][8][9]. This spin gap formation in the ID chain in Sr 14 Cu 24 0 41 is attributed to the charge order of Cu 2+ and Cu 3+ in the chain.…”

Section: Resultsmentioning

confidence: 92%

NMR/NQR Study on Magnetism of Spin Ladder Sr_2.5Ca_11.5Cu₂₄O₄₁

Kumagai

Tsuji

Maki

2000

Zeitschrift Für Naturforschung A

View full text Add to dashboard Cite

show abstract

“…Both spin ladders and chains extend in the c direction. A large spin gap in the ladders of the order of 400 K was observed in this system [14,[49][50][51]. Figure 3 shows the thermal conductivity of Sr 14 Cu 24 O 41 as a function of temperature measured along the three crystallographic axes [44].…”

Section: Heat Transport In S = 1/2 Spin Laddermentioning

confidence: 99%

Low-temperature heat transport of spin-gapped quantum magnets

Zhao

Liu

et al. 2016

Sci. China Phys. Mech. Astron.

View full text Add to dashboard Cite

This article reviews low-temperature heat transport studies of spin-gapped quantum magnets in the last few decades. Quantum magnets with small spins and low dimensionality exhibit a variety of novel phenomena. Among them, some systems are characteristic of having quantum-mechanism spin gap in their magnetic excitation spectra, including spin-Peierls systems, S = 1 Haldane chains, S = 1/2 spin ladders, and spin dimmers. In some particular spin-gapped systems, the XY-type antiferromagnetic state induced by magnetic field that closes the spin gap can be described as a magnon Bose-Einstein condensation (BEC). Heat transport is effective in probing the magnetic excitations and magnetic phase transitions, and has been extensively studied for the spin-gapped systems. A large and ballistic spin thermal conductivity was observed in the two-leg Heisenberg S = 1/2 ladder compounds. The characteristic of magnetic thermal transport of the Haldane chain systems is quite controversial on both the theoretical and experimental results. For the spin-Peierls system, the spin excitations can also act as heat carriers. In spin-dimer compounds, the magnetic excitations mainly play a role of scattering phonons. The magnetic excitations in the magnon BEC systems displayed dual roles, carrying heat or scattering phonons, in different materials.

show abstract

Spin gap and dynamics inSr14−xCaxCu<

Cited by 148 publications

References 53 publications

( Sr / Ca ) 14 Cu 24 O 41 spin ladders studied by NMR under pressure

( Sr / Ca ) 14 Cu 24 O 41 spin ladders studied by NMR under pressure

NMR/NQR Study on Magnetism of Spin Ladder Sr_2.5Ca_11.5Cu₂₄O₄₁

Low-temperature heat transport of spin-gapped quantum magnets

Contact Info

Product

Resources

About

Spin gap and dynamics inSr14−xCaxCu<

Cited by 148 publications

References 53 publications

( Sr / Ca ) 14 Cu 24 O 41 spin ladders studied by NMR under pressure

( Sr / Ca ) 14 Cu 24 O 41 spin ladders studied by NMR under pressure

NMR/NQR Study on Magnetism of Spin Ladder Sr2.5Ca11.5Cu24O41

Low-temperature heat transport of spin-gapped quantum magnets

Contact Info

Product

Resources

About

NMR/NQR Study on Magnetism of Spin Ladder Sr_2.5Ca_11.5Cu₂₄O₄₁