#################################################### # Takeshi Egami # requesting 8 days, at minimum=6 days # beamline 33ID, Diffuse scattering from superconducting cuprate # instrument 33ID-D kappa #################################################### # top:/home/www/beamtime-requests/req00821.txt # UNICAT Member Beam Time Request #821 # created Thu Aug 18 10:30:14 CDT 2005 #################################################### apsrun: 2005-03 beamline: 33ID collaboration: Yes collaborator_Paul: ON collaborator_Pete: ON contact: egami@utk.edu days: 8 description: Anomalous x-ray scattering at the Cu K-edge of diffuse scattering from YBCO1248 will be studied as a function of temperature. Our recent data show clear non-phonon contribution peaking around Tc = 80K, disappearing around T(psuedo-gap) = 160K, suggesting strong correlation between the local Cu displacement and superconductivity. Non-phonon contribution to diffuse scattering is consistent with inhomogeneous local Cu displacement with the correlation length of 20A. YBCO1248 (YBa2Cu4O8) is a stoichiometric compound, and the observation of lattice distortion in this compound is a major surprise, supporting the idea of intrinsic electronic inhomogeneity in the cuprates. This is a difficult measurement, but finally we are getting fantastic data, worth the effort paid so far. equipment_required: displex, vortex detector experiment: Diffuse scattering from superconducting cuprate foreign_nationals: Ferenc Stercel, Zsolt Marton, Cinzia Metallo hazards: No hazard is expected. instrument: 33ID-D kappa instrument_other: minimumdays: 6 name: Takeshi Egami nonmembers: submit: Submit unacceptable_dates: z34ID_details: #REMOTE_HOST: egamipc1.engr.utk.edu #REMOTE_ADDR: 160.36.8.58 #CONTENT_LENGTH: 1259 #HTTP_USER_AGENT: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 1.1.4322)