Phonon dispersions and anomalies of ${\text{MgCNi}}_{3}$ single-crystal superconductors determined by inelastic x-ray scattering

Phonon dispersions and anomalies of ${MgCNi}_{3}$ single-crystal superconductors determined by inelastic x-ray scattering

Hawoong Hong, Mary Upton, Ayman H. Said, Hyun-Sook Lee, Dong-Jin Jang, Sung-Ik Lee, Ruqing Xu, and T.-C. Chiang

Phys. Rev. B 82, 134535 – Published 28 October 2010

Abstract

The intermetallic perovskite ${MgCNi}_{3}$ superconducts at $\sim 8 K$ despite its high Ni content; the underlying mechanism is thought to be pairing via phonons. Prior theoretical calculations of the phonon-dispersion relations showed soft modes, anomalies, and regions of imaginary frequencies possibly relevant to the superconducting transition, but there are large discrepancies among the calculations. To clarify this issue, we have performed inelastic x-ray scattering measurements of the phonon-dispersion relations. The results confirm soft longitudinal acoustic modes near $(0, \frac{1}{2}, \frac{1}{2})$ and $(\frac{1}{2}, \frac{1}{2}, \frac{1}{2})$ but disprove a pronounced transverse acoustic anomaly near $(\frac{1}{4}, \frac{1}{4}, \frac{1}{4})$ .

Received 23 August 2010

DOI:https://doi.org/10.1103/PhysRevB.82.134535

Authors & Affiliations

Hawoong Hong^1,*, Mary Upton¹, Ayman H. Said¹, Hyun-Sook Lee^2,†, Dong-Jin Jang^2,‡, Sung-Ik Lee^3,§, Ruqing Xu^4,5, and T.-C. Chiang^4,5

¹X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, Illinois 60439, USA
²Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea
³National Creative Research Initiative Center for Superconductivity, Department of Physics, Sogang University, Republic of Korea
⁴Department of Physics, University of Illinois, 1110 West Green Street, Urbana, Illinois 61801-3080, USA
⁵Frederick Seitz Materials Research Laboratory, University of Illinois, 104 South Goodwin Avenue, Urbana, Illinois 61801-2902, USA

^*hhong@aps.anl.gov
^†Present address: Materials Science and Technology Research Division, Korea Institute of Science and Technology, Seoul 136-791, Republic of Korea.
^‡Present address: Department of Physics, Sungkyunkyan University, Suwon 440-746, Republic of Korea.
^§Deceased.

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand

Issue

Vol. 82, Iss. 13 — 1 October 2010

Reuse & Permissions

Access Options

Author publication services for translation and copyediting assistance advertisement

Physical Review B

covering condensed matter and materials physics

Phonon dispersions and anomalies of ${MgCNi}_{3}$ single-crystal superconductors determined by inelastic x-ray scattering

Hawoong Hong, Mary Upton, Ayman H. Said, Hyun-Sook Lee, Dong-Jin Jang, Sung-Ik Lee, Ruqing Xu, and T.-C. Chiang

Phys. Rev. B 82, 134535 – Published 28 October 2010

Abstract

Authors & Affiliations

Article Text (Subscription Required)

References (Subscription Required)

Issue

Access Options

Physical Review B

covering condensed matter and materials physics

Phonon dispersions and anomalies of MgCNi3 single-crystal superconductors determined by inelastic x-ray scattering

Hawoong Hong, Mary Upton, Ayman H. Said, Hyun-Sook Lee, Dong-Jin Jang, Sung-Ik Lee, Ruqing Xu, and T.-C. Chiang

Phys. Rev. B 82, 134535 – Published 28 October 2010

Abstract

Authors & Affiliations

Article Text (Subscription Required)

References (Subscription Required)

Issue

Access Options

Authorization Required

Other Options

Download & Share

Images

Figure 1

Figure 2

Figure 3

Figure 4

Log In

Search

Article Lookup

Paste a citation or DOI

Enter a citation

Phonon dispersions and anomalies of ${MgCNi}_{3}$ single-crystal superconductors determined by inelastic x-ray scattering