Valence transition of YbInCu4 observed in hard X-ray photoemission spectra.
نویسندگان
چکیده
Yb 3d and valence-band photoemission spectra of the first-order valence-transition compound YbInCu4 have been measured with hard x ray at an excitation energy of 5.95 keV. Abrupt changes are clearly observed in both spectra around the transition temperature T(V)=42 K, in comparison with ultraviolet and soft x-ray photoemission (VUV-PES and SX-PES) spectra. From the Yb 3d spectra, the Yb valence has been estimated to be approximately 2.90 from 220 down to 50 K and approximately 2.74 at 30-10 K. We propose that Yb 3d hard x-ray photoemission spectroscopy is a very powerful method to estimate the valence of Yb with high accuracy. On the other hand, the Yb2+ 4f-derived peaks in the valence-band spectra exhibit a remarkable enhancement below T(V). The shape of the valence-band spectra is different from those of the VUV-PES and SX-PES spectra above T(V), reflecting the In 5s and 5p contributions.
منابع مشابه
Determination of the surface band bending in InxGa1−xN films by hard x-ray photoemission spectroscopy
Core-level and valence band spectra of In x Ga1-x N films were measured using hard x-ray photoemission spectroscopy (HX-PES). Fine structure, caused by the coupling of the localized Ga 3d and In 4d with N 2s states, was experimentally observed in the films. Because of the large detection depth of HX-PES (∼20 nm), the spectra contain both surface and bulk information due to the surface band bend...
متن کاملElectronic structure changes across the metamagnetic transition in FeRh via hard X-ray photoemission.
Stoichiometric FeRh undergoes a temperature-induced antiferromagnetic (AFM) to ferromagnetic (FM) transition at ~350 K. In this Letter, changes in the electronic structure accompanying this transition are investigated in epitaxial FeRh thin films via bulk-sensitive valence-band and core-level hard x-ray photoelectron spectroscopy with a photon energy of 5.95 keV. Clear differences between the A...
متن کاملBulk electronic structure of the dilute magnetic semiconductor Ga(1-x)Mn(x)As through hard X-ray angle-resolved photoemission.
A detailed understanding of the origin of the magnetism in dilute magnetic semiconductors is crucial to their development for applications. Using hard X-ray angle-resolved photoemission (HARPES) at 3.2 keV, we investigate the bulk electronic structure of the prototypical dilute magnetic semiconductor Ga(0.97)Mn(0.03)As, and the reference undoped GaAs. The data are compared to theory based on th...
متن کاملInvestigation of surface and non-local screening effects in the Ni 2p core level photoemission spectra of NiO
We studied the Ni 2p core-level spectra of NiO using cluster model calculations and X-ray photoemission spectra. The calculations were performed for a NiO6, a NiO5, and a NiO6:NiO5 cluster, which allows studying the bulk, the surface, and the non-local effects in the spectra. The photoemission spectra were taken with soft (or hard) X-rays to enhance the surface (or bulk) contribution. The calcu...
متن کاملTemperature Dependence of Magnetically Active Charge Excitations in Magnetite across the Verwey Transition.
We study the electronic structure of bulk single crystals and epitaxial films of Fe_{3}O_{4}. Fe 2p core level spectra show clear differences between hard x-ray (HAX) and soft x-ray photoemission spectroscopy (PES). The bulk-sensitive spectra exhibit temperature (T) dependence across the Verwey transition, which is missing in the surface-sensitive spectra. By using an extended impurity Anderson...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Physical review letters
دوره 93 24 شماره
صفحات -
تاریخ انتشار 2004