Nuclear resonant inelastic X-ray scattering at high pressure and low temperature.

Wenli Bi,Quanjie Jia,Jung-Fu Lin,Changqing Jin,Wenge Yang,Michael Y Hu,Viktor Struzhkin,E Ercan Alp,Richard Ferry,Jiyong Zhao

doi:10.1107/s1600577515003586

Abstract

A new synchrotron radiation experimental capability of coupling nuclear resonant inelastic X-ray scattering with the cryogenically cooled high-pressure diamond anvil cell technique is presented. The new technique permits measurements of phonon density of states at low temperature and high pressure simultaneously, and can be applied to studies of phonon contribution to pressure- and temperature-induced magnetic, superconducting and metal-insulator transitions in resonant isotope-bearing materials. In this report, a pnictide sample, EuFe2As2, is used as an example to demonstrate this new capability at beamline 3-ID of the Advanced Photon Source, Argonne National Laboratory. A detailed description of the technical development is given. The Fe-specific phonon density of states and magnetism from the Fe sublattice in Eu(57)Fe2As2 at high pressure and low temperature were derived by using this new capability.

Highlights

Nuclear resonant inelastic X-ray scattering (NRIXS) was developed about two decades ago (Seto et al, 1995; Sturhahn et al, 1995)
The parent compounds of these superconductors exhibit a tetragonal to orthorhombic structural transition accompanied by a magnetic transition forming spin density wave (SDW) state from the Fe sublattice
The extra junction between the cold finger and the diamond anvil cells (DACs) reduces the cooling efficiency shown by the temperature gradient from the cold finger to the DAC: 9 K on the cold finger while 20 K on the diamond anvil cell

Summary

Introduction

Nuclear resonant inelastic X-ray scattering (NRIXS) was developed about two decades ago (Seto et al, 1995; Sturhahn et al, 1995). The technique uses Mossbauer isotopes as probes while using synchrotron radiation as the source of excitation. Directional sensitivity and rich information content are hallmarks of this technique. The technique has gained extensive momentum in recent years and the number of places to perform such measurements has proliferated. Measurements of NRIXS spectra under extreme conditions of pressure (Mao et al, 2001) and temperature (Chumakov & Sturhahn, 1999) have been performed. In an attempt to combine several environmental parameters, high pressure and high temperature have been achieved using laser heating

Methods

Results

Conclusion