1.
Phys Rev Lett
; 84(9): 1990-3, 2000 Feb 28.
Artigo
em Inglês
| MEDLINE
| ID: mdl-11017678
RESUMO
The oxygen isotope effect on the relaxation rate of crystal-field excitations in the slightly underdoped high-temperature superconductor HoBa2Cu4O8 has been investigated by means of inelastic neutron scattering. For the 16O compound there is clear evidence for the opening of an electronic gap in the normal state at T(*) approximately 170 K far above T(c) = 79 K. Upon oxygen isotope substitution ( 16O vs 18O) T(c) decreases marginally to 78.5 K, whereas T(*) is shifted to about 220 K. This huge isotope shift observed for T(*) which is absent in NMR and NQR experiments suggests that the mechanism leading to an isotope effect on the pseudogap has to involve a time scale in the range 10(-8)>>tau>10(-13) s.
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Phys Rev B Condens Matter
; 34(9): 6130-6136, 1986 Nov 01.
Artigo
em Inglês
| MEDLINE
| ID: mdl-9940489
8.
Phys Rev B Condens Matter
; 32(9): 5837-5844, 1985 Nov 01.
Artigo
em Inglês
| MEDLINE
| ID: mdl-9937831
9.
Phys Rev B Condens Matter
; 35(10): 5334-5336, 1987 Apr 01.
Artigo
em Inglês
| MEDLINE
| ID: mdl-9940729
10.
Phys Rev B Condens Matter
; 35(16): 8804-8806, 1987 Jun 01.
Artigo
em Inglês
| MEDLINE
| ID: mdl-9941258
11.
Phys Rev B Condens Matter
; 53(2): R534-R537, 1996 Jan 01.
Artigo
em Inglês
| MEDLINE
| ID: mdl-9983074
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Phys Rev B Condens Matter
; 54(9): 6721-6727, 1996 Sep 01.
Artigo
em Inglês
| MEDLINE
| ID: mdl-9986692
13.
Phys Rev B Condens Matter
; 36(7): 4011-4013, 1987 Sep 01.
Artigo
em Inglês
| MEDLINE
| ID: mdl-9943366
14.
Phys Rev B Condens Matter
; 36(13): 7241-7243, 1987 Nov 01.
Artigo
em Inglês
| MEDLINE
| ID: mdl-9942475