TY - JOUR
T1 - Spin gap of Sr14-xAxCu24-yMyO41 (A = Ca,La
T2 - M = Zn,Ni) studied by thermal conductivity
AU - Kudo, K.
AU - Koike, Y.
AU - Maki, K.
AU - Tsuji, S.
AU - Kumagai, K.
N1 - Funding Information:
This work was supported by a Grant-in-aid for Scientific Research of the Ministry of Education, Science, Sports and Culture, Japan, and also by CREST of Japan Science and Technology Corporation.
PY - 2001/1
Y1 - 2001/1
N2 - We have investigated the spin gap and hole pairing in the ladder of Sr14-xAxCu24-yMyO41 (A = Ca,La: M = Zn,Ni) from the thermal conductivity measurements. The observed thermal conductivity κ has been analyzed to be composed of κph, κspin and κhole due to phonons, spins and holes, respectively. κph shows a peak or a shoulder at approximately 30 K in every direction of every crystal. κspin is observed only along the c-axis and exhibits a broad peak around 100-150 K. The broad peak is depressed through the Zn substitution more markedly than the Ni substitution. The spin gap in the ladder estimated from κspin is approximately 400 K and independent of x. This corresponds to the spin excitation from spin-singlet to spin-triplet. κhole becomes marked at high temperatures for larger x(Ca) values. The spin gap in the ladder estimated from κhole decreases with increasing x(Ca). This corresponds to the gap due to the dissociation of spin-singlet pairs, i.e. the dissociation of hole pairs.
AB - We have investigated the spin gap and hole pairing in the ladder of Sr14-xAxCu24-yMyO41 (A = Ca,La: M = Zn,Ni) from the thermal conductivity measurements. The observed thermal conductivity κ has been analyzed to be composed of κph, κspin and κhole due to phonons, spins and holes, respectively. κph shows a peak or a shoulder at approximately 30 K in every direction of every crystal. κspin is observed only along the c-axis and exhibits a broad peak around 100-150 K. The broad peak is depressed through the Zn substitution more markedly than the Ni substitution. The spin gap in the ladder estimated from κspin is approximately 400 K and independent of x. This corresponds to the spin excitation from spin-singlet to spin-triplet. κhole becomes marked at high temperatures for larger x(Ca) values. The spin gap in the ladder estimated from κhole decreases with increasing x(Ca). This corresponds to the gap due to the dissociation of spin-singlet pairs, i.e. the dissociation of hole pairs.
UR - http://www.scopus.com/inward/record.url?scp=0034824059&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0034824059&partnerID=8YFLogxK
U2 - 10.1016/S0022-3697(00)00165-7
DO - 10.1016/S0022-3697(00)00165-7
M3 - Article
AN - SCOPUS:0034824059
SN - 0022-3697
VL - 62
SP - 361
EP - 364
JO - Journal of Physics and Chemistry of Solids
JF - Journal of Physics and Chemistry of Solids
IS - 1-2
ER -