Cold Neutron Triple-Axis Spectrometer
CTAX | CG-4C | HFIR
The scientific communities that use the CG-4C instrument include condensed matter physics and materials science. Typical applications of this instrument include studies of nuclear and magnetic structures, quasi-elastic scattering, and lattice and magnetic dynamics in a variety of materials, including superconductors, transition metal oxides, multiferroics, thermoelectric materials, and low-dimensional quantum magnets. An 11 T vertical, asymmetric field cryomagnet with a 3He insert option is dedicated to CG-4C for studies requiring a magnetic field.
Nuclear structure studies:
Determination of lattice distortion and phase transitions.
Example:
* Hong T., Zhu L. Y., Ke X., Garlea V. O., Qiu Y., Nambu Y., Yoshizawa H., Zhu M., Granroth G. E., Savici A. T., Gai Z., Zhou H. D., "Structural and magnetic properties in the quantum S=1/2 dimer system Ba3(Cr1-xVx)2O8 with site disorder", Physical Review B 87, 144427 (2013).
Magnetic structure studies:
Magnetic propagation vector determination and order parameter measurement as a function of temperature or applied magnetic field.
Example:
* Taniguchi T., Kadowaki H., Takatsu H., Fak B., Ollivier J., Yamazaki T., Sato T. J., Yoshizawa H., Shimura Y., Sakakibara T., Hong T., Goto K., Yaraskavitch L. R., Kycia J. B., "Long-range order and spin-liquid states of polycrystalline Tb2+xTi2-xO7+y", Physical Review B 87, 060408 (2013).
MacDougall G. J., Garlea V. O., Aczel A. A., Zhou H. D., Nagler S. E., "Magnetic order and ice rules in the multiferroic spinel FeV2O4", Physical Review B 86, 060414 (2012).
Phonon excitations:
Measurement of collective, low-energy lattice dynamics, including phonon lifetimes.
Example:
* Ma J., Delaire O., May A. F., Carlton C. E., McGuire M. A., VanBebber L. H., Abernathy D. L., Ehlers G., Hong T., Huq A., Tian W., Keppens V. M., Shao-Horn Y., Sales B. C., "Glass-like phonon scattering from a spontaneous nanostructure in AgSbTe2", Nature Nanotechnology 8, 445-451 (2013).
Magnetic excitations:
Measurement of collective, low-energy spin dynamics.
Examples:
* Matsuda M., Fishman R. S., Hong T., Lee C. H., Ushiyama T., Yanagisawa Y., Tomioka Y., Ito T., "Magnetic dispersion and anisotropy in multiferroic BiFeO3", Physical Review Letters 109, 067205 (2012).
* Wang C. H., Lumsden M. D., Fishman R. S., Ehlers G., Hong T., Tian W., Cao H., Podlesnyak A., Dunmars C., Schlueter J. A., Manson J. L., Christianson A. D., "Magnetic properties of the S=1/2 quasisquare lattice antiferromagnet CuF2(H2O)2(pyz) (pyz = pyrazine) investigated by neutron scattering", Physical Review B 86, 064439 (2012).
* Nakajima T., Mitsuda S., Haraldsen J. T., Fishman R. S., Hong T., Terada N., Uwatoko Y., "Magnetic interactions in the multiferroic phase of CuFe1-xGaxO2 (x = 0.035) refined by inelastic neutron scattering with uniaxial-pressure control of domain structure", Physical Review B 85, 144405 (2012).
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