X-ray Assisted Scanning Tunneling Microscopy and Its Applications for Materials Science: The First Results on Cu Doped ZrTe3

Abstract

Synchrotron X-ray Scanning Tunneling Microscopy (SX-STM) is a novel imaging technique capable of providing real space chemically specific mapping with a potential of reaching atomic resolution. Determination of chemical composition along with ultra-high resolution imaging by SX-STM can be realized through excitation of core electrons by incident X-rays when their energy is tuned to an absorption edge of a particular atom during raster scanning, as is done in the conventional STM experiments. In this work, we provide a brief summary and the current status of SX-STM and discuss its applications for material science. In particular, we discuss instrumentation challenges associated with the SX-STM technique and present early experiments on Cu doped ZrTe3 single crystals.

Thermal Dynamics of Charge Density Wave Pinning in ZrTe3

“…As shown in Fig. 1(c), the chain structure of the Te-Te dimers and a few impurities (point defects) can be clearly resolved, with a higher resolution than previous STM results on ZrTe3 [23,24]. The majority of the impurities are likely to be Te vacancies because the vapor pressure of Te is higher than that of Zr and Te can escape from the crystal during the growth process.…”

Thermal transport and mixed valence in ZrTe$_3$ doped with Hf and Se

“…27,28 Below T CDW , ZrTe 3 shows a filamentary-to-bulk SC at T c ∼ 2 K with local pair fluctuations; SC first condenses into filaments along the a-axis, and then becomes phase coherent below 2 K. Bulk SC with an enhanced T c is observed by applying pressure, intercalation, substitution, and disorder, with suppression of CDW order. [29][30][31][32][33][34][35][36][37][38][39] Pressure-induced re-entrant SC in ZrTe 3 implies the possible unconventional Cooper pairing mechanism, 29 yet the ultra-low-temperature thermal conductivity indicates multiple nodeless gaps in ZrTe 3−x Se x . 36 ZrTe 3−x Se x displays SC with the T c up to 4.4 K for x ∼ 0.04, where the CDW-related modes in Raman spectra is observable while the long-range CDW order vanishes.…”

Enhanced superconductivity and electron correlations in intercalated ZrTe3

“…Bulk SC can be induced in ZrTe 3 by applying physical pressure, intercalation, doping, and disorder [36][37][38][39][40][41][42][43][44][45][46][47]. A pressure-induced reentrant SC in ZrTe 3 implies a possible unconventional SC mechanism [36], while the ultralowtemperature thermal conductivity indicates multiple nodeless gaps in ZrTe 3−x Se x [44].…”